Let me give you a real example, from two days ago.
A home with circa-1940 service suddenly lost power to one side of the fuse box. The customer was planning to do a service change this fall- but wouldn't really be able to afford one today.
I get the old service apart, and find that one of the clips on the main fuse holder was ever so slightly bent, and wasn't making contact with the buss. No signs of overheating or arcing....turns out the had just done some remodeling, and pulled the 'main.' Probably got dropped, or something like that.
Now I could have done the service change...the customer had already been "sold"...but would that have been ethical, when the problem was fixed in fifteen minutes?
