Imagine the following scenario.

You've had a long day at work. The rain is pouring down outside. You hop into your car and turn onto the road home. Despite the miserable weather, lack of traction and bad visibility, the trip goes smoothly.

About halfway home, you turn into a narrow stretch of road with heavy traffic. At this point, the roads are so narrow that the two directions of travel are separated by a landscaped, tree-filled central reservation. In your direction, the road consists of what should really be considered a single lane with narrow shoulders, but it's often used as a two-lane road without any shoulders. Of course, under these road conditions, nobody would be stupid enough to try to pass on this narrow stretch of road.

As you turn onto this narrow road, you almost freeze, because you see the yellow headlights of another car coming toward you, still some distance away. This is the side of the road for your direction of travel. You should not see yellow headlights here. You should only see red tail lights. Yet here are the yellow headlights of a madman hurdling toward you.

Act II

You are not sure what the wisest decision is: should you stop your car and exit it? Is there some way to warn the people behind you so they don't try to pass? You start gently braking, being careful not to lose control on the wet, slippery road.

All the while the thoughts are spinning around in your head, the driver on the wrong side coming toward you gets ever closer. You see the water splashing around his tires, forming little droplets that appear to just hang there in the air when he cuts through them, ever decreasing the distance between you two. As he is close enough, you see he's doing something on his phone. And he's swerving all over the place.

Briefly, he looks up and sees you. Then he looks back down at his phone, continuing to zigzag across the road, toward oncoming traffic.

Since this road is wide enough to barely fit two cars, you decide that the best thing to do will be to stick to your side of the road like you don't have anything else in life, and keep slowing down. You won't be able to stop in time, but hopefully, however drunk the other driver is, they will drop their phone, take the wheel of their car and stick to their side. If they do, you'll both escape a frontal collision.

The other driver gets closer and closer, and does not get rid of his phone to steer. He's on the right of the road, then on the left, then again on the right. You start braking harder. Eventually, you think to hell with traction and brake as hard as you can. The brakes of the car in front of you are squealing just as much as yours. But they're still on your side of the road.

When you are close enough that it's clear the other driver won't get out of your side of the road – and they're still glued to their phone – you swerve.

They lose control again, and skid into the same side you were swerving into.

Your vehicles touch.

At first, lightly.

Then gradually harder.

Then they are entangled and made to stop by the laws of physics. In an epic battle of forces and a loud crash, they have shed their kinetic energy as sound, heat and deformation.

You go over your handlebars. He goes over his.

I lied to you; there are no cars here. This was a bicycle–bicycle collision on a bicycle path, which are fortunately less lethal than car–car collisions. I was unharmed, and the other cyclist said he was unharmed as well. My bike did not suffer any apparent damage. The other cyclist was not playing on his phone, he was trying to hold a yellow umbrella to protect himself against the rain. He had a dry torso, but you'll have to ask him if it was worth the cost of having to eat pavement. This happened to me yesterday, but something along these lines happen every day on bicycle paths.

Lesson

Sure, you could claim the other cyclist was at fault, and he was. But if there's anything history tells us, it's that people will cause accidents. With that in mind, we have created an official policy in Sweden when it comes to motor traffic, which states that

In every situation a driver might fail. The road system should not.

This means the roads should make it ridiculously easy to drive safely even if you're not at your mental peak. It's not an excuse to drive tired or drunk, but it does save a lot of lives. The roads should be designed such that even if a driver makes an accident, it's easy for them to recover, while giving surrounding traffic a chance to deal with the situation.

Bicycle paths are just not designed according to this maxim. If a cyclist fails, an accident is going to happen. Bicycles are considered vehicles by law, but city planners continuously ignore them, and then squeeze them in wherever there was some space left. The road system will not save them. There's just no way around it.

In this case, there are three obvious and easy fixes that would have prevented the accident:

1. Better signage. Technically, it wasn't illegal for the other cyclist to be on the "wrong" side of the road. All bicycle paths are by default – even if they are way too narrow for it – bidirectional. A few signs that prohibit cyclists from going in the wrong direction (and encourages them to turn onto the right side of the road) would probably do something.
2. Widening the bicycle paths. Most bicycle paths are wide enough for only one cyclist at a time. You can imagine the fustration when different cyclists are going at different speeds, or, such as in this case, the danger when there is something (like opposing traffic) blocking part of the bicycle path.
3. Providing small "off ramps" every now and then. These off-ramps would let cyclists steer off the path in case there is something blocking the path further ahead. At the moment, the side of the bicycle path is often curb, which is a guaranteed crash if you're trying to jump up it at the angles required. (Of course, this would not excuse blocking the bicycle path. It's just a belt-and-suspenders safety measure in case something else has gone terribly wrong.)

Until these things are fixed, safety-conscious bicyclists will continue to ride on the public roads. The surrounding traffic is much more predictable, and the roads are actually designed with safety in mind.

Travel-along-ability

Besides safety, there's another important reason many cyclists prefer to ride on public roads. Ever notice how, when you're in a car, you may often find yourself being frustrated with other cars, but very rarely are you frustrated with the road system itself? It's because the public roads are designed to make it simple and smooth to go from point A to point B.

Rarely do public roads suddenly end in a guard rail or make sharp 90 degree turns on what's otherwise a straight, long stretch. You do not often find roads with huge rocks or clumps of concrete in the middle of them – and when you do, they are very clearly marked out and if you listen to the radio they might be broadcasting an emergency message about dangerous debris on the road. Bicycle paths often have this kind of dangerous crap on them intentionally.

When public road traffic is re-routed, it's often with strong, clear reflective signage. When bicycles are re-routed … they usually don't get any signage at all. They're just expected to figure it out on their own.

If you're on a bicycle, it's not uncommon for road signs to direct you onto a road where it would be illegal for you to continue to ride. The only option is getting off your bike and leading it forward. Sometimes you can continue to ride, but the signs force you to keep riding in circles. As in, it's literally illegal to do anything other than keep riding in circles around a block. (Or get off your bike, obviously. It's always an option to just get off your bike, but why is this viewed as a default option? Can you see the frustration in car drivers if they regularly had to stop, unbuckle their seat belts and get out of their cars, walk a few feet and then get back into their cars? Just to be able to continue toward their destination.)

Would you imagine the chaos if two lanes of opposing high-speed traffic suddenly had to share a single lane without any signals controlling who moves first? Or someone planting a huge oak in the middle of the road and just expecting traffic to deal with it on their own?

Important thoroughfares are often given right-of-way, with connecting roads having to yield or even stop before entering. How frustrating wouldn't it be if it was the opposite, so the important thoroughfare had to yield to joining traffic?

These are not technically all safety hazards, but if you wanted to design a road that's annoying to drive on, take a cue from bicycle paths.

There's a Swedish word for this which basically translates to "travel-along-ability", and concerns how easy it is to travel along somewhere and reach your destination with minimal effort. As long as public roads have a reasonably high "travel-along-ability" and bicycle paths have no "travel-along-ability", cyclists will ride on public roads.