One word for 'automatic nature' of doing certain things? [duplicate]
In this kind of situation, we often say we're doing something by muscle memory, even if the action isn't a physical one. However this usually has a positive implication, meaning you're so well practiced that you make the correct move without thinking.
You could also say you're doing something by rote, although implies a highly repetitive action.
And, of course, in chess when there are such automatic moves during the opening phase of the game, they are called book moves.
For the case where the move is bad, you might call it impulsive or unthinking.