Those conventioneers are partially right. It's true that initial negotiations are the best opportunity to catapult yourself into a new tax bracket. Later on, when you manage to finagle yourself a 20% raise it will mean more if your starting salary was $60,000 than if it was $40,000. So one of the best ways to move up is to move on.

However, if you love your job, boss, coworkers, benefits, 3-minute commute, in other words, everything but the salary then you must convince your boss that you're worth that extra thousand shekels a month.