Awful grinding on a new unit usually means either a bad jar bearing or a stripped drive coupler. tbh Both are manufacturing defects more than user error.
Quick tests. With power off & rotate the blade by hand. Smooth is good and scratchy or loose is bad. With the jar seated and empty, do a single tap of the power. If it screams even with no load, stop. Do not try to lubricate anything or open the base. Oil does not reach sealed bearings and can contaminate food.
Use the warranty and ask for a replacement jar or base after sharing a short video and the serial. That is typically resolved fast. Not worth risking.
I go by cost versus utility. If I can replace it cheaply and haven't touched it in months, it's out. Fix what I can with stuff I already have instead of buying organizers. Keeps things simple without extra spending.
