Stupidity. I'm not known for making good life decisions.why did you continue to have kids with her?
I convinced her to have our fourth in the moment, because I thought it would make me stay with her. So, basically baby trapping myself.
Then I wasn't careful one time and didn't think about pregnancy at all.
Had a vasectomy, and a week later found out about #5.
Didn't do the semen analysis because we weren't having sex anyway. Eventually got around to it and was told the chance of pregnancy was low, get tested in a few months, and I might want to use a backup method just in case. I misinterpreted that as "nothing is 100% effective" rather than "it didn't work".
Found out the hard way that open-ended vasectomies don't accomplish anything but a very low, but not low enough, sperm count and mutilated nuts for a second time.
So yeah, stupidity.