Let's not start the cyclists vs motorists flame.

Cycle lanes, especially protected ones, are there to encourage cycling.

That is the idea. The implementation of cycling lanes often has unintended consequences. Getting the details right is important or we end up with "cycle lanes to nowhere", lanes more dangerous than what was there before, drivers so angry about the lanes that the next round of politicians ban cycling completely, or several other possible futures I'm not even aware of. (Note that all of the above objections are general, they can apply to lanes for any purpose - only by careful work as the car lobby able to avoid them 100 years ago...)