Gets soft before orgasm ?

Just curious if this is common ?

So everything is super great and excitind and usual while im getting naughty with my man, whether its masturbating, oral, intercourse... but ive noticed that for like a brief moment right as he is cumming his member like relaces a bit ? Like it goes from rock hard to a tiny softer, then he cums ? Is that normal/healthy ?

I couldnt find anything on it online, and its not worth asking a Dr. IMO. Also kinda awkward thing to ask him 😅