I get a LOT of mail. Not as many as some, I'm sure, but a lot. I can pick up 20 items for me when I go to the post office. More may show up at the house. These range from bills to statements to begs (political, social, environmental... and no, I can't just throw them away; some of them have merit) to political information to catalogs (I keep the most recent one of these... and at a guess I'm on over 100 current mailing lists!) to just plain trash.
Anyhow, I try to triage it when I bring it home. The bills on top, the statements next, the cruft below.
Somehow before I left our 2 week trip to WorldCon etc., I didn't notice 2 credit card bills.
Somehow, after we got home, they didn't tumble to the top of the list.
I found them 1.5 days before they were due, and mailed them off, paying the cards off in full, one day before. Ooops. They arrived and were credited the day after they were due, and each of these cards hit me with a $39.00 charge for the late payment.
I have before called up banks and credit unions to say "Come on, I *always* pay as soon as I get the statement -- I never got it this time" -- but this time was my goof, and I just can't bring myself to do that. Shy, yes, but if I feel I have the moral high ground I'll stand up to "them". But not this time.