engines - What does it mean when stockfish evaluates a move as an

I stumbled onto this position from a game posted on reddit. Stockfish gives the best move as cxd4, which it evaluates as +2. If you play cxd4, it then says cxd4 was an inaccuracy (only being +1)

Stockfish: In-Depth look at a chess engine (1)

Stockfish: In-Depth look at a chess engine (1)

How do chess engines beat one another? Why can't they evaluate every possible move, play perfectly and stalemate every time? - Quora

Computer chess - Wikipedia

josh's site

Stockfish - Open Source Chess Engine

The neural network of the Stockfish chess engine

The Chess Engine's Final Horizon :: Luke Salamone's Blog

Bradley Lovell - Polecat