Why is the number of events different from the number of goals achieved in Google Analytics?

Question

Google Analytics

In Google Analytics, you can set up events and goals. One way to create a goal is when we specify that the goal is reached when an event fires.
In theory, both counters should match: the number of events that have occurred and the number of goals achieved upon the occurrence of these events. However, in practice, it always turns out that the number of goals achieved is less than the number of corresponding events.
Can you tell me why this is happening and how to interpret it?

Answer 1

Because the goal is the UNIQUE achievement of the event.
For example, a person added 5 items to the cart: there will be 5 add to cart events, and the goal will be one "add to cart"