The phrase "actual execution" refers to the real or physical act of carrying out or completing a task or plan. It means putting something into action or making it happen in reality. Full definition
However, we also noted a lag between pressing one of the buttons on the back and actual execution of the command. (laptopmag.com)
The rainbow sprinkles were an attempt to create a sprinkle layer in the cake which turned out to be better in thought than in actual execution. (acookingmizer.com)