CYCLE rewards are distributed proportionally to vault TVL. The multiplier (0.5x, 1x or 3x) are used to scale that vaults TVL when considering what portion of the reward distribution that vault will receive. For example, if one vault has 1 million TVL and another has 100k, the first one will get 10 times the CYCLE distribution if they're both 1x but if that 2nd vault had a 3x weight, it's TVL would be considered as 300k when determining what portion of the rewards it receives.