Sometimes very tricky problems that require quite a bit of ingenuity are removed simply because they're exercises in physics/maths. Well, what is the fundamental difference asking about a specific 'concept' as opposed to solving a hard problem? They both involve similar skills and I daresay that solving problems is all you really need to do anyway and the former will come naturally as a result. If the goal of this website is to be a place where people can improve at physics, then we should have a more lenient homework policy.

Plus, problem solving is an enjoyable process and this website's popularity would skyrocket if we were more open to it.

I still respect the homework policy in so far as closing questions that clearly show no research or attempt. But we can't keep closing questions whose answer exists somewhere.