When compelting a work log, the "Technician Resolving This Request" and the "Executed Time" fields are mandatory but the "Time Taken To Resolve" is optional.

 

"Time Taken To Resolve" must be mandatory as well since it is this field in which the technician is expected to report their hours.

 

With the field being optional, techs can simply ignore it meaning that "Time Spent" reports are unreliable.