To best support the production function, which runs on planning and scheduling, the maintenance function must plan and schedule its work. Ad hoc work assignments undermine this, so issue each job assignment via work order instead. The notable exception would be in the case of an emergency or priority No. 1 repair; in such a case, a supervisor needs to walk the work order through while the work is underway.
But isn't a work order just paperwork? No, and in some facilities the work orders aren't even paper. A work order is a formal order to do specific work (thus, its name).
Today, nearly all maintenance departments use a computerized maintenance management system (CMMS). In this system, you prioritize, assign, track, and analyze maintenance work. When the work is completed, the filled-out work order provides valuable information to the CMMS.
Bypassing work orders means bypassing the CMMS. That's a sure way to plunge maintenance and production into costly chaos.