[Por_sha911]

I can't accept that they can't split a check (even after the fact). The server was either lazy or untrained and I would have asked to speak to someone higher up.

Poor service justifies low or no tip but, without an explanation the server will assume you are a jerk or forgot. Asking to speak to the manager and privately expressing your assessment of the service would have been much better. As far as the tip is concerned, I will leave 5 or 10% with a note why it was low (0 only when something especially egregious has taken place and a note and a conversation with the manager). I've probably left no tip at a full service restaurant 2 times in the last 40 years. I have left 10% with a note and a conversation with the manager (not frequently but on a number of occasions). I don't tip when they took my money and handed me a bag.

I don't accept "but they rely on tips to make decent money". Should a salesman get a commission if they did a garbage presentation and didn't get the contract? If you can't give good service then maybe you need to do something else. If nothing else, say "I'm sorry I didn't do X but..."