A lock is used to prevent a sequence of actions from being triggered again before it’s completed.

For instance, if you have an object designed to spin and then catch fire, as shown here:

Without a lock, a player could potentially re-trigger this sequence while the object is still on fire. To prevent this and ensure the entire sequence completes before it can be initiated again, you would need to add a lock to these steps:

With this lock in place, players can only interact with the object and trigger the execution after the entire sequence, including the fire effect, has fully completed.