If the engine window has vertical space, the program displays the rating history of the search. So you can see from when the rating stabilized. This gives the user an idea of the complexity of the position (or in rare cases the blindness of the engine).

 

 

The Larsen-Spassky game from the 1970 match is probably the most famous real short game (under 20 moves) among the absolute world elite. The rating history for White shows the disadvantage before 12...h4(Larsen-Spassky before 12...h4): But only after 22 moves the consequences are clear.