I have a few.

One is abbreviation hell. Nobody is going to spend the time trying to decipher what you mean when you use over several abbreviations. It is just better if you'd explain than expecting people to understand aside from commonly used abbreviations that are easy to understand.

Another is overstepping your limits for the sake of getting a partner. Compromising your own standards is perhaps one of the worst things you can do when it comes to trying to find dates. Like you're suddenly okay with dating single parents but you don't like children. You're suddenly okay with dating religious people but you're not religious. Things like that. Because it means you're desperate and you're setting yourself up and setting them up for a bad date.