I have found particles trapped in filter
1 micron = 1 millionth of a meter = 4 millionths of an inch.
It's not the parts you can see. Any automotive filter will trap the birds and rocks.
The small particles in the micron range act as a fine polishing compound. If you can even imagine putting polishing compound in the engine then the price of the filter is nothing. Yes, your oil/filter budget can run some money, but nothing close to the price of a worn out or blown engine.