How often do you follow up on rejected offers?

[Brendan Miller]

I've submitted several full price offers in the past month on MFH properties via MLS that I haven't been successful on. I'm curious how often you (or your agent) follow up on offers with the listing agent prior to closing in case the accepted offer falls through? I know it happens, but does anyone do this as a standard practice, or do you just move on and focus on the next lead?