Most can be considered common courtesy. Sidney Diver covered alot of the most frequent peeves. Bad finning techniques are always first on everyones list for good reason.
These are some of the things I come across that make me peevish. As a new diver....
1. Try your best. I gladly dive with new divers and will help them improve their after cert. skills. But you are wasting my time if you don't try to learn from your experiences or mine.
2. Be on time. Whether you are meeting other divers are a local site or boarding a dive boat. And don't get bent out of shape when we continue without you.
3. Buy and use dependable gear and keep it in good working order. Nothing is more frustrating than diving with someone whose gear is always breaking down or needing field service. In todays sue-happy society, I no longer tweak and repair others gear on site. If your octo is always free flowing, get it fixed. Don't keep showing up and expecting me to tweak it for the days diving. And no, you can't use my spare reg.
4. Learn to pack the gear you need and bring spares in case something happens. I have extra fins straps and a spare mask for my use, not yours. And extra fin straps ( even o-rings) cost me money so if you have to have them, at the very least pay me for them. I much prefer you cover your own a$$.
5. SECURE YOUR GEAR! There's absolutely no excuse for your gauges and octo to be swinging in the breeze. Clips, retractors and octo holders don't cost that much...buy and use them. You'll damage the environment and your gear. This is one of my biggest pet peeves and one of the biggest signs of a new and/or careless diver.
6. Learn from those around you and don't be afraid to ask for help. Honest efforts to improve your skills will be viewed as a strength, not a weakness.
7. Be honest to yourself and others about your abilities.
8. Remember that Anyone can abort a dive at Anytime for Any Reason. You may not feel well, you may feel the dive is above your comfort level or you may just have a 'feeling' not to do a dive. Doesn't matter. The final choice to get in the water is your, no one elses. My peeve is those who try to pressure their buddies or others in the group to continue to dive.