To each according to his contribution

This phrase means that people should receive or be rewarded according to the work they do, or the amount they contribute. It means that the more work, effort or time that someone puts into something, the more they should be rewarded for it. For example, if two people work on a project together, they should both get paid the same if they contribute equally, but if one person worked harder or put in more time, they should be paid more than the other person.