Sorry if this is a dumb question or duplicate. If it is a dupe, it's been down voted beyond search-ability.
I've posted a comment or two here and there, and got up from my computer and realized I misstated something, or left something out, etc. etc. And, my comment was closed to editing. In those cases I merely deleted them, and rewrote, but I'm wondering why there is a time limit in general?
And, in particular, why so short?