Some things can't be evaluated until they're done. Applying for grants is the canonical example: in order to get money for your proposal, you more or less have

Some things can't be evaluated until they're done. Applying for grants is the canonical example: in order to get money for your proposal, you more or less have to implement the proposal first. Similarly, senior devs expect junior devs to spin their wheels writing software that will likely have to be re-written. It's also more cost-efficient than the alternative of discuss-as-you-go hand-holding since a junior dev's time is relatively worthless.