What about a unicorn shitting a rainbow onto your head?

The problem with "but sometimes..." arguments is that the "sometimes" rarely happens. For example, at www.hetregentbijnanooit.nl someone tracked how often it rained during their daily commute of 2x 45 minutes of cycling. Over an 11-year period, 90.3% of the commutes were dry - and that number would be even higher for people with a shorter commute, or those willing to wait a few minutes for the current rain squall to pass. Invest $100 in a luxury rain coat and the problem is solved.

Besides, in a country like The Netherlands the car is the less than ideal transport option! It is expensive, you keep getting stuck in traffic, you have to search for an available parking space, you can't park right at the door of your destination, and so on. For intra-city people movement, a bike is almost always the most convenient option.

Does it sometimes suck? Yeah, of course, but it sure beats getting stuck in traffic every single day.