Can you improve a supercomputer evaluation on your own move? While watching the Chess World Championship, a few news outlets provide updates on how supercomputers are evaluating the board position. The example I'm looking at is using the Sesse Supercomputer, which evaluates the strength of one side over the other measured in pawns. For example, though I don't remember the exact numbers, at one point in game 8, Caruana had an advantage of roughly +2, however after the ill-advised move h3, the computer reevaluated their position to be roughly equal.

That made me wonder: Can you improve your evaluated position on your own turn, or do you only stand to weaken it?

It seems to me that if you had a move available which strengthened your position, that would be included in the evaluation. My assumption (of which I'm not certain), is that the computer expects you to take the best possible move, so doing so would simply maintain the advantage you already have. Taking any move aside from the strongest would weaken it.

Is this the case?
The point of an evaluation is to rate one sides chances of winning and to select the best chance of winning for that side. All the engine can do is calculate up to a certain point and then rate the position.
So yes you can definitely improve your evaluation because the engine may have missed something past its search depth.

If an engine had infinite depth there would be no point of an evaluation.