Why do contributors delete their own posts?


A significant contributor who shall remain unidentified deletes posts shortly afterwards. It’s not done with the intent of correction, but for the purpose of limited viewing. I wonder what rationale warrants this behavior. It certainly not for the benefit of providing context for later viewers who might want to learn from the thread. 
128x128celander
I agree that one never knows who (author or system) deletes the posts. But I strongly suspect members are deleting their posts as the content doesn’t seem to warrant a deletion by another means pertaining to violating a system forum policy. 
05-12-2019 6:15pm, Geoff wrote:

“jitter [sic] provides much humor with his 80% grammatically correct sentences.”

☝🏻☝🏻And speaking of grammatically incorrect phrases. Lol

I cannot post more than 3 successive posts, per the GK rule. 
Don't be jealous, it took years for me to build myself up to 80%.

This may have already been mentioned, but I think that if a poster deletes his/her own post, it says something like "post removed and the date".  But if the mods delete a post there is no evidence it was ever there in the first place..