So many schools of thought with none being absolutely right or wrong.
Way back in the day, the accepted wisdom was every 3-5 years but the lubes improved dramatically and it was pushed out to 5-7 years.
For a daily wearer Automatic I only get 5 to 5.5 years before there is change in timekeeping of some description which will vary from stopping randomly overnight to a slight change in timekeeping in either direction(+ or -).
I have gone 13.5 years on a Co-axial that's worn fairly infrequently before the timekeeping slowed down from a rock solid +3.5 to creeping closer to 0.
Rolex are the only ones on record for suggesting 10 years. That's not necessarily an endorsement.
All others that have solid reputations are suggesting shorter time frames under normal operating conditions.
The problem is that what is normal for one person can be poles apart for another and this is reflected in some way or another in the language they use when making their recommendations.
If one drills down into it all that is
