Currently, Zammad contains only the selectors “is” and “is not” for integer fields. Use cases for these are probably not very common, except for “is / is not 0”. Adding the usual comparison operators for integers, i. e. “greater than”, “less than”, “less or equal” and “greater or equal”, would be a useful feature.
Example use case:
The customer object is expanded with an integer field for “Tickets this month” which is e. g. populated by the API. The customer’s contract specifies that they may open up to four tickets per month. Once they open a fifth ticket, a note is automatically added telling the agents that the customer exceeded their limit, preventing unpaid work.
(I’d have used a more built-in use case, but there are no built-in integer fields appearing in the trigger dropdown. Probably because they’re not very useful 
)