I mean in theory you could, but there are time limits, mental limits, psychological effects in play. That opportunity is not always there so you can't expend th

I mean in theory you could, but there are time limits, mental limits, psychological effects in play. That opportunity is not always there so you can't expend the mental energy (and time) to treat every position as an entirely new chess puzzle by making yourself believe that it has a winning solution. Most of the time there isn't but you can't know that there isn't so most moves would consist of you giving up (because there is no such move). Then you'd get used to giving up. Yet you don't know when to give up exactly and move on because there may or may not be a valid answer. When you know there is a valid answer though, your strategy for time planning changes, your psychological approach changes because you know there is a solution. When you know there is a solution, you can afford to expend the mental energy that produces hyperfocus which is costly and can't be sustained for the entirety of the game. Your dopamine circuitry kicks in and you search for the solution that you know exists. A programming analogy may be: When you are programming you are solving problems but you don't approach it with the assumption that every line of code can be buggy. You just assume things are right and keep on writing best you know how - or you'd never make progress. Sometimes there are bugs, only later you can find and fix them. Asking a chess player to assume every position is critical is like checking every line of code for bugs each time you read them just in case. If you know there is a bug you have methods to search for it, but you can't program while checking every line over and over again by assuming they introduce bugs.