You have probably noticed that messages will pop up whenever the Sole Survivor does something to increase the companions affinity. For example if you pick a lock the message will read "Piper liked that" if she is your companion.

However, I noticed that this message does not appear all the time, there rather seems to be some kind of cooldown time intervall between messages. That is, whenever I pick two locks in short succession there will be no second message after the first.

Does that mean that affinity is unaffected by the second action? Is there some sort of cooldown phase? Or is it just the message?