Interest and motivation comes largely from success. You try something, it works, it feels good so you continue doing that. The school's role is to enable this "easy success" early on so kids will continue.
And from a practical point of view, let's consider this. The mindset one is indulging with this is that it's okay to quit if something is hard. But how does indulging that mindset, change it? What happens when the easy successes end and things not only get hard, but very hard? Are you not simply creating false expectations?
We all saw the "draw the owl" picture. Step 1 is easy step 2 is easy but then the rest appears impossible. Why not make a series of small, doable steps that lead to the result? The "hardness" of many things is not exponential, it's linear or even less dramatic.