It’s easy to think that lack of motivation connotes lack of interest: if I’m not motivated to work on something, it must mean I’m not interested in it.
The truth is more complicated. I might lack motivation because I’m tired. I might lack motivation because the goal is so distant it’s hard to see it…or to get motivated to move toward it. I might lack motivation because an obstacle is out of my control. I might lack motivation because I’ve tried hard in the past and not seen any progress. I might lack motivation because the modern world is great at distraction.
I know people who have assumed a lack of motivation is a sign that they should change paths. Maybe not: maybe it’s because of one of myriad other reasons, and I need to address that to regain my motivation.