The amount or number of coins held within a wallet and the time they have been held there go towards adding up to what is known as 'coin weight' - this will include all the coin block inputs? within the same address listings - if for instance there are change addressess?, of a different public address, they will not be included and will have to be combined into the same coin block to be eligible using coin control?.
If you are taking part in the Proof of Stake? consensus and network, the more coin weight your client wallet has, the more of a chance of a stake it will have. The numbers can be deterministically variable on different setups - if a wallet has 100 ION within it, and another competing wallet has 1000 ION held, the latter client wallet will have a better of a chance of a stake reward, and may well Stake more frequently than the less coin weighted client wallet.. (Both these client wallets in this scenario need to be unlocked for staking and the coins have 61 confirmations to be eligible).