[vostok]

It depends on what you were able to negotiate. You might have a guaranteed bonus in your first year, but you might rely on your employer's generosity in future years. In some cases, the bonuses may be based on certain targets, but those targets can become impossible to meet if your employer changes certain aspects of your situation.

Even in the very unlikely event that you have an airtight contract, there are instances where the employer simply will not pay you. Legal action might be the only recourse in this situation. Sometimes you are required to go through arbitration and sometimes you have to sue.