there is the other side as well, PM : build me a bike. Dev: here is a spaceship. PM: but i wanted a bike. Dev: bike make no sense if u can travel using a spaceship.
At the risk of being overly nitpicky (because I understand and agree with the general point you're getting at):
That spaceship _is_ super awesome and far superior to a bike if you need a solution that'll get you a far distance in a short amount of time.
But what if the need is something that's safe, cheap, and doesn't require complicated infrastructure to support? A bike might be a better solution.
Blame the PM if they're not making those priorities and needs clear, though.
Sometimes you know that they ask a bike but will change the specifications later, so you try to prevent the mess.
Trust me, I have a lot of experience in building 3-wheeled space-bikes ;D .