There is quite specific machining to difficult positions in chess that should be mentioned. A difficult position occurs when at the surface it seems that there are many viable moves to be analyzed. Think of being a kid and thinking which pawn to move first. Then you learn opening theory and it gets a little easier.

But you can still encounter a position where you could take multiple pieces, all leading to different trades or some forces moves. Another scenario is when you're in a closed position and there are many, many micro adjustments you could make. An ai might know that you should move the A pawn and you might not even be considering it.

Basically, positions where GothamChess starts speaking with a Russian accent to channel the Russian grandmasters.