Too Long; Didn't Read
By staking, you are locking up your PoS collateral in exchange for actively partaking in verifying transactions and creating new blocks. As such, you're becoming an honest participant in the network since you have a stake to lose if you are not. Staking secures the network, backs the price of its native token and contributes to decentralization. In exchange for the stake, you receive staking rewards or percentage yield, typically in the same coin, paid regularly and almost always higher than any interest rate of traditional savings accounts or payments on treasury bonds.