The phrase "a deeper motivation" is correct and usable in written English.
You can use it when discussing underlying reasons or driving forces behind actions, decisions, or behaviors.
Example: "While the surface reason for her decision was financial, there was a deeper motivation rooted in her desire for personal fulfillment."
Alternatives: "a more profound reason" or "a stronger incentive."
Occasionally the veil has slipped, revealing what might be a deeper motivation for Republican lawmakers.
And there was a deeper motivation, which he links to his first political inspiration, the former Labour leader Hugh Gaitskell and his warning that integration into Europe would mean "the end of a thousand years of history", with Britain no longer an independent nation.
There's a deeper motivation for stacking refuse.
There is a deeper motivation in using this ploy; to show a pattern of "violent conduct" on the woman's part so that the abuser can use it as evidence against her in a divorce or child custody battle.
Ultimately, Aronson explains a deeper motivation behind the show: "We live in a time when the world is getting smaller through new technologies.
While these beautiful women certainly think about the effect exercise has on their appearances, a deeper motivation has to exist -- not just for better, more long-lasting results, but for a happier workout.
But there is a deep motivation within Clemens, and at the moment, the pursuit of 300 is nudging him forward.
In his view, drastic weight loss depends on a deep motivation to take care of oneself, plus a sense of accomplishment as the pounds slip off.
As opposed to persistence, grit is something that is backed by a deep motivation to change things around us.
Yes, book after book after book has been written about finding a deep motivation to change.
I finally had a deep motivation for my studies, but I only had one year left to answer the burning questions I had about the world.
