I have a dark secret. I used to have CenturyLink DSL around 5 years ago, and the tech asked me if I had restarted the modem during one of the many stints where I would get bits per second rather than the "10mbps" we were supposed to get
I lied every time. I'm sorry CenturyLink tech support employee, but man did CenturyLink suck, and man am I absolutely sure that it never fixed the issue.
At one point I filed a complaint with the FCC and got a letter from CenturyLink telling me that they knew about the complaint!
The metrics are the only important part! How else are we supposed to know how good the line is unless we constantly stress test the line by collecting data? Your ability to use the line is not a useful metric, so we don't worry about that.