The actual contribution rate is where our analytical lens focused. For every £100 wagered on a participating slot, between £0.50 and £1.20 is diverted into the jackpot pools, split across the three tiers based on a pre-defined proportion. The operator discloses this ratio within the game rules for each title, and we discovered the figures to be steady across the library. The Mini tier takes the smallest portion, typically 15% of the allocation, the Major captures 35%, and the Mega uses the remaining 50%. This weighting guarantees that the largest prize expands at the fastest rate, which is visually dramatic and marketing-savvy, but it also means the middle tier provides what we regard as the most compelling blend of accumulation velocity and realistic win frequency. We must stress that the jackpot drop is guaranteed; there is no maximum cap where the pool would be capped or removed. The progressive meter builds up until a random trigger event takes place, and the full displayed amount is awarded to the single lucky participant, after which the tier goes back to its seeded base.