What is the result of sending a transaction to a function on a contract?

Sending a transaction to a function on a smart contract primarily modifies the contract's data. When a transaction is executed on the blockchain, it invokes a specific function defined within the smart contract, which may change the state or update variables. This process typically involves a change in the ledger where values can be stored, such as account balances or other state variables maintained by the contract.

In contrast to just querying data, which would not alter the contract's state, sending a transaction is a way to interact with the contract actively. While returning data is an associated function call, it does not capture the essence of what occurs when you send a transaction aimed at modifying the contract’s internal data.

Regarding execution time, transactions are processed as part of the blockchain's consensus mechanism, which means that they are not instantaneous; they take some time to be confirmed within a block. In addition, the assertion that a transaction will always fail if the contract is not verified is misleading. The verification of a contract relates to its public availability and auditability rather than its ability to function or process transactions, so it does not directly affect the transaction's success regarding state modification.