A VIP tier is a step in a loyalty programme reached by staking a certain turnover. A higher tier usually gives a larger rakeback, faster support and higher limits.
The value is one subtraction
The rakeback percentage minus the house edge. If you play a game with a 1% edge and get 0.5% back on stakes, your effective cost is 0.5%. If the rakeback is 0.05%, practically nothing changes.
The other half: what the tier costs
The required turnover costs you the house edge on average. €100,000 of turnover in a game with a 1% edge costs an average of €1,000. The question is not "is the tier good" but "does it give back more than reaching it cost".
The calculation basis decides everything
The same 5% calculated on stakes means a hundred times more than calculated on the house edge. You will not find that difference in the marketing text — ask support in writing. See the loyalty programme calculator.
What the programme does to you
A VIP system is built to grow turnover and in many programmes the tier drops when turnover falls. That means constant pressure to play. If you notice you are playing for the tier rather than for the game, take the self-assessment.
A comparison of the programmes is on the VIP programmes page.