Why do cartridge manufacturers give a range for VTF?

@celander ,

I'm not having any issue, just a question for my own benefit.

@millercarbon,

Your explanation makes good sense. Thank you sir.

Well, normally there is a small range from any manufacturer, but there is also an exact recommended tracking force in any manual i have seen (no matter MM, MI, MC ....). There is also recommendation to burn in a new cartridge with higher tracking force and then lower it down to recommended tracking force. A used cartridge with weak suspension can be used with lower tracking force. So there is a case for almost any situation.  I always use recommended tracking force for 99% of my carts. 

I've noticed that there seems to be a post removed almost every time I post. Do I have a stalker? A'gon is looking into it.

Agree with Chak that most carts have a range but then there will usually also be a recommended number, invariably pretty much in the middle of the range.

I just shoot for that middle ground number every time or slightly higher.