If M-deleting is your issue, then before you M delete make sure all the product in location is the same. Shampoo and conditioner is best example since you have upc's out in the backroom all the bottles look the same. If you scan it and theres no double beep then verify upcs before moving on. M delete errors is just simply you missed a bottle and then someone on another pull later finds the bottle you missed. If you find a lot mixed up let your Leader know so they can look into who backstocked it and can follow up with that team member on proper backstocking. Also, you say you recently stopped doing that, first off I recommend you still Mdelete when the situation calls for it. It's unproductive to exit out and LOCU particularly if your relocating it and still missing the same bottle. Second remember errors are on a 14 week cycle, so the system will pick up the errors for 14 weeks.
Hope this helps and I commend you on wanting to have 0 errors.