I keep coming back to this topic, because it is one that I see nearly every day. You should really keep your watches clean. Besides, the fact that a watch full of body cheese is disgusting, it also causes your watch bracelet to wear out prematurely (I touched on this in A clean watch lasts forever and Tribology). A well made watch bracelet should provide you with many, many years of use. A Rolex bracelet, for example, should really provide you with 30 years of use if you keep it clean and wear it tight to the wrist.
We tend to rate watch bracelets by how much life is still in them. A new bracelet is 100%, a bracelet ready to fall apart and break is 0-10%. A ten year old bracelet should be at about 70% or so under normal use. A co-worker of mine showed me her Rolex yesterday, it is 7 years old and I would rate it at 85%. She takes good care of her watch.
Lets look at a brand new bracelet:This watch, however, which I looked at yesterday is only 10 years old and the bracelet is more like 30-40%:
I’ll spare you the pictures of the body cheese that was packed inside the bracelet, but pretty much their was no open spaces at all. All that dirt and grime is just wearing away the steel and causing this bracelet to wear out prematurely. Keep your watches clean!