Cartridge new or used ?


How do I know if a cartridge is new or used and number of hours played ? 1- If it is bought from an individual or 2- Could it be that a HiFi store sells used or a "Demo" without anyone knowing it? 3- Is a cartridge that remains on the shelf of the store for 3 or 4 years, retains its same performance or its internal parts, can harden and lose their flexibility of reading? 4- Is it easy with a magnifying glass to see the wear of a cartridge, if so what would be the best magnification to use?
audiosens
Boy, first 'used underwear', now 'used food'....... You guys really have a deeply felt disgust towards used cartridges.

As far as I'm concerned this is the preferred mainstream opinion: by all means stay away from used cartridges! Less competitors in the market place means lower prices.....

It really depends on the seller.

I have purchased used cartridges with success as well as new cartridges.

I am considering sale of a cartridge (purchased new) which has been used for 19 record sides (I keep track) so about 6-7 hours. The sale of high quality used cartridges well cared for and used lightly does happen.
daveyf
who knows why some people sell stuff so cheap, problems financial or health or even drugs, who knows.
Over the years I have bought many audio items, usually from ebay, that were so stupidly cheap I just had to buy them even though I may not have even needed them.
Did I get burnt on any transaction?
Not one if memory serves me correctly!
And fyi the Koetsu plays perfectly well as delivered
Again if used cartridges makes you nervous I completely understand and commend you for staying out of that market BUT do not belittle the market or sellers/buyers of said used cartridges as a whole.
Thank you
edgewear"Are you really worried these records will be damaged from being played by a slightly worn modern diamond stylus with some advanced profile?"

No I am not worried, concerned or troubled at all by a used stylus because I do not buy used cartridges, underwear, or tires.  
@clearthink Let's make it clear: your cartridges are used, each time you play next record your stylus getting more and more used, not sure how can you live with it ?  I'm sorry, i know you don't want to use used cartridges, but actually you do.