You can be written up for several things including medication errors, not following hospital policy, failure to carry out orders, not signing off your orders, not doing your shift end chart checks, not meeting the basic needs of your patients, and attitude. Any person you work with can write you up, your manager will be the one to discuss the issue with you and decide if further action should be taken. Just remember to always follow hospital policy and if you're not sure about something, ask. There are no dumb questions and it's better to be safe than sorry.