Not getting to have “schooling”. I was “homeschooled”, in that my parents kept all 8 of us kids at home and didn’t bother to provide much in the way of education beyond reading and basic math. The lack of real education I was able to overcome, but the gross lack of any socialization has left me struggling with poor social competency to this day.
I’ve run into similar: on the account creation page there was no character limit on the input box nor stated in the password requirements, but on the login page the password input box was limited to 14 characters. So you could successfully create an account with a long password, you just couldn’t log in because it wouldn’t let you enter the whole password.