One of the most inefficient activities we can perform in our treatment room is trimming before waxing services.  If you are using the appropriate wax and have good technique there is no need to trim.  The shorter the hair the harder it is to catch it all up.  Longer hair comes out cleaner.   I wax hair when it's long, 1/2" or longer,  without trimming while maintaining client comfort.  Trimming can take up to 10 minutes of your time and creates a huge mess, hair all over the place no matter how hard you try to keep it contained.  If you have hairs remaining after waxing, follow up with a bit more wax to try and catch them up, if you can't get them all, then they will have to wait until next time.  If you are using soft wax, follow up with hard to remove strays and visa-versa.