Minting is the opposite of a token-burn. Legitimate minting follows published rules: staking rewards, block-rewards, or issuing a stablecoin against deposited collateral.
Discretionary minting is a risk to check on every token you trade. If an owner address can call mint without limit, your holding can be diluted arbitrarily, and several "hacks" have simply been an owner minting and selling.
Verification is concrete: read the contract on a block-explorer, look for mint functions and who can call them, and check whether ownership is renounced or sits behind a timelock and multisig-wallet.
Related: token-burn, admin-key-risk, erc-20, timelock