[xor1]

This is true for lots of things though, right? Programming languages, spoken languages, mathematics, muscle mass...use it or lose it, but it gets easier to re-learn/re-gain everything each time. Plus you don't necessarily have to forget or lose it if you're able to set aside the time to maintain it.

[Rarebox]

Exactly. Having the experience of solving difficult algorithmic puzzles under time pressure makes parts of software engineering (writing working code, debugging) easier, so you can focus on the hard parts. Algorithmically, almost anything written in the real world is trivial in comparison.