Why would 560SEC Seat leather wear out?

Hi,
Just saw a 1990 560SEC with only 82K miles. Wood is faded and cracked, indicating suboptimal care.
More concerning to me is the complete wear through of the door side bolster of the driver seat.
Any ideas why/ when this occurs? I can't imagine the leather on an MB seat to completely wear though (big hole -exposing fabric below) under normal circumstances.
How much might it cost to repair this or would one replace the seat altoghether?
Thanks in advance for any input
farrukh

[fredsegal]

I bought my 1991 420 SEL with 150,000+ mi. from a banker who weighed 120-130, the leather was almost showroom. I weigh twice that plus some and the drivers seat is showing some minimal wear after only a year. Conclusion; if it was my big butt getting in and out of that seat instead of the bankers mini butt the seats would look much more worn.

thanks Fred, for the rather insightful and vivid reply... :-)
guess that explains it then!

Unless you can a used one in good condition - you can have the side panel replaced with matching leather at a good auto upholstery shop - cheaper than a new seat. I believe there was a thread last year with a link to a company that sells new leather seat covers(replacemant not add on) and horsehair pads for Mercedes. If I remember right the leather covers for one seat was around $400 -550 and the horseair pads were $100-200 - OK guys - don't jump on me if I am wrong - I am trying to go from memory - and as I get older the ol' memory may slip now and then!!!