[throw1234567891]

Paint is usually slippery. There are special standards for how slippery a paint painted on the tarmac can be. But it’s calculated for cars, not racing bicycles with teeny-weeny tires. Could have been easily the paint.

[NetMageSCW]

Perhaps they should have used some type of traction paint.

[throw1234567891]

There are other problems with that in wet conditions.

[olyjohn]

I mean, one of the first things they teach in motorcycle safety classes is that the road stripes are slippery and could cause a crash, especially in the rain. Even if there us a standard for how slippery it can be, it still doesn't match the traction of the road surface.