Maybe the lack of motivation and inspiration should be telling them something?
Think about it this way: People do things for rewards (tangible or intangible; some sort of goal they want to reach.) If they're not getting the rewards, the tendency is for them to quit and try something else... like the horse who isn't getting enough grass in one section of the pasture. Rather than staying in one place and grazing the old ground, the horse will try to go somewhere else where there's a better reward (food).
One reason that the entrepreneurs try and fail and end up being successes is that they know WHEN to say "okay, enough." Part of that is judged by their lack of personal motivation.
That lack of motivation MAY be telling you that the job/opportunity just isn't that rewarding to you and you might need to think about doing something else.
The Five Minute Mentor