While everyone else was focused on getting rich, Devin had a much more personal reason for going through the portal. Each time he made the leap, he did a quick search on his father. The first time we learned of Devin's background, it's on a newspaper article with the following headline, "Crooked Businessman Chooses Suicide Over Prison," and it was followed by a story of how his dad got caught up in a scandal that resulted in two businesses going under.
This was the same end result that happened in Devin's reality, as we learned when another character said, "Corruption runs in the family" right to his face. His father's death was the same across several different universes, until Devin finally encountered one in which his father was still alive.
Devin was looking for closure because, in his reality, the last thing he told his dad in the midst of his scandal was, "I f***ing hate you." His dad went out right after that and ended up dead. Later, Devin managed to confront his father in a universe in which his suicide attempt had failed, and he got locked away in prison. Devin realized he could be a different man, in contrast to the various business plans he got involved in with Noel that weren't always ethical.
This didn't exactly gel with Noel's increasingly erratic and disturbing behavior, who replaced Devin with an alternate version — a technique he mastered earlier in the film.
