Start phasing out old efforts from unreliable devices
While this isn't a problem for longer segments I think about half the shorter segments (less than 2 mins) are owned by old efforts on phone apps.
Looking at longer efforts there aren't many where the KOM hasn't changed in the last few years. However, where I live every other short segment is from 2013 or so and 9 out of 10 times this is on an iPhone/Android app. Plus they are by random people - not the usual suspects.
These are obviously not bonafide efforts. Maybe it's time to start looking at removing some efforts on older devices. I guess the problem is down to GPS accuracy / sampling rate, but it is IMO something that needs fixing.