Linn Sondek question

What is it about a Linn Sondek LP12 that requires it to be tuned up?  I was at a Linn specialist recently and was amazed at the amount of Linn Sondeks he had just in waiting for "tune ups" or whatever they needed.  There must have been at least twenty.  So, how often does this have to be done?  Is it the springs, weather conditions etc.  I never see other tables requiring this kind of attention for what seems to be required on a regular basis.  Can it be done by the owner?  Seems like a lot of fiddling.  The setup that was there sounded great.  There is a specialist on youtube that posts many Linns and the sound quality is fantastic, but at what cost?  Like I said, I have never seen that many tables requiring attention in my life.  So what his the thing with these tables?
I have never had mine adjusted except at purchase from the dealer and it is still 95% in tune 30+ years later.
How do you know?  I've setup a lot of Linn LP12's and I would wager to bet that yours is in need of a tuneup, (probably many years ago).  You would be surprised how much of a difference it will make.

These things age and go out of alignment very gradually over time.  Our ears get used to this gradual change.
This is one of the reasons I let mine go.  No offense to noromance but I was taught that you push down on the platter 1/2 way between the spindle and tonearm base to check alignment. But that only indicates the suspension and won’t reveal anywhere on the other parts .  I will say that properly tuned they are a very tough table to beat for musicality.
I own a Linn Sondek and two Ariston's (RD11 and RD11S). I like to have their suspensions set rather tight, with minimal bounce. I feel this tightens up the bass and produces a more focused presentation from the mids up.