A local variable/number/value is not normally held in memory outside of the event block it is used in, so yes it resets to 1 each time. This is a key property of how local variables work as opposed to global variables. Note that this can be overwritten with the "static" option set, as described in the manual.
https://www.construct.net/en/make-games/manuals/construct-3/interface/dialogs/event-variable
That makes sense, thank you!