Moisture meters are deceptively scientific and accurate to the point that they will cause you to deny your own common sense. I used them for many years until I learned how they really work and why I was having watering problems.
The meters do not measure water, they measure conductivity of electricity between two types of metal in the tip of the probe. Because water is a good conductor, the assumption is that the wetter the soil, the greater the conductivity. While that is generally true, other factors such as mineral salts, hard water and soil compaction also affect conductivity. Thus, the metters work in some circumstances but not others and it is very difficult to distinguish between them.
Meters also tend to break down after constant use and can become expensive.
To determine soil moisture deep in larger pots, use a simply soil probe such as Soil Sleuth. It is simple, plastic and lasts forever. It is also more reliable.
As for laziness, I don't have an answer!
