Getting the answer and working backwards teaches you to use what others have created within very narrow guide rails. Figuring out the answer for yourself (with some minimal guidance) teaches you to create new things. We should strive for the latter.
Getting the answer and working backwards teaches you to use what others have created in novel ways to find new solutions to old problems. Figuring out the answer for yourself (with some minimal guidance) teaches you toy problems with answers have answers. We should strive for the former.