"motivations underlying" is correct and usable in written English.
You can use it when discussing the underlying motivations behind a certain action or way of thinking. For example: "The motivations underlying her decision to pursue a career in teaching were deeply rooted in her childhood experiences."
Few showed sociopathic tendencies, the staff members said, and the extent of their misconduct and the motivations underlying their actions varied greatly.
This entry will, first, discuss the positive and negative motivations underlying proposals for world government.
On the other hand, it tells us nothing concerning the real motivations underlying firm's hiring choices.
Nevertheless, considering values is a way to understand what matters to people and the motivations underlying their decisions.
Fig. 2 There are several pathways of emergence and entry of biofuels onto national agendas with different motivations underlying their promotion.
Taken together, the findings from the three experiments suggest that results from real-effort tasks require a careful evaluation and interpretation of the motivations underlying the observed performance.
We then highlight areas of convergence and divergence among the scenarios and stakeholders' views on climate change, not to compare scientific and lay knowledge but to investigate what understandings and motivations underlie stakeholders' views on adaptation.
The proximity of his workplace and his home is convenient, but there is a serious political motivation underlying it, too.
In fact, the clear motivation underlying Leona Helmsley's will — her desire to pass her wealth on to dogs — is more common than might be expected.
The motivation underlying human cruel behaviour is complex.
However, this move leaves two important questions unanswered: (i) What is the motivation underlying the thematic-expletive distinction?
