Being "lazy" simply means that, for whatever reason, you've made the rational evaluation that the energy necessary to do a task is greater than the reward you'd get from the task.

In some cases, that can be because someone's ability to reason about cost and reward is impaired, due to mental disabilities like depression. In other cases, it may be because the work they're expected to do simply doesn't align with their priorities in life. "Laziness" can even be a form of resistance against power in some cases—why should someone exhaust themselves putting 110% effort into making thousands of Big Macs every day, just to make the shareholders of McDonald's richer?

In any case... one thing that definitely doesn't make people any less "lazy"? Telling them what horrible and worthless people they are.