In article om,
says...

If the chain is worn, then it is more costly to keep riding on it than
to replace. I do not have 10sp (no need), but on my bikes riding hard
in hilly terrain 1000-1500 mi is about where the chain *needs* to be
replaced; very rarely I can get up to 2000 mi. I measure regularly,
replace when needed. And due to that my chainrings and cassette cogs
last a very long time.

If you clean your chain properly and then oil it, you can get a very long
life out of it. Same thing for the rest of your drivetrain. I had a 7spd
dura-ace chain that laster over 15k miles with no measureable wear.
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Alex