I do the same. I don’t have an established opinion on everything, and it can take some time to form one, so if someone presses me for an answer to, say, “What did you think of that movie?” shortly after I’ve left the cinema, it’s always “pretty good.”
I think I use ‘pretty good’ to pretend I have an opinion about something, rather than it being a moral judgement:
How was the film? Pretty good vs.
How was the film? Good.
I do the same. I don’t have an established opinion on everything, and it can take some time to form one, so if someone presses me for an answer to, say, “What did you think of that movie?” shortly after I’ve left the cinema, it’s always “pretty good.”