As everyone has said it happens, but I do have a slightly different take on it. I have two ways to hook on differing water styles.
Classic flowing water letting the fly swing I do nothing but clamp the line firmly till you feel the full weight of the fish. Then lift. And it may sound obvious but I was amazed last season watching others play fish how little pressure they applied to a fish, barley having a bend in the rod. Get that rod bent. Imo of course
Second is slacker water and retrieving your fly. Square casts and figure of 8 retrieve. In this situation I strike, I know that everything ever written or said about salmon fishing takes this is not the done thing. Well I meet a angler going through a pool, and as we talked he had a fish take! Well the fish was struck! So he played it landed it then released it. Afterwards I said? I hope you don't mind me saying but you struck that fish, oh yes he said, If a fish pulls I pull back! Simple . He suggested he was easy 1 in 8 losses. I never done it for years and as I say now on retrieving only. But its working for me. I'm currently on 39 landed for 4 losses. For the last 2 seasons.