Is motivation logical? Well, it's mitigated by logic -- hopefully-- but that's not the same as being driven by it. There's quite a bit of evidence of brain reward systems running on chemicals (ie dopamine) in kind of a 'ka-ching ka-ching' fashion. There's scientific evidence of reward system irregularities being implicated in various disorders. Is a person less logical because they fail to experience reward or motivation in the more typical ways?
Ah, and then there's the issue of drives. Just about everyone has heard the term 'drive' applied to things like sex, but there's also a drive toward monogamous/ faithfulness, supported by its own system of neuroeptides. (Some of the early research on that came from studying prairie voles, and why it was that they formed pair bonds and nurtured their young for a long time when other related species didn't.)
Of course I've also written recently about the issue of sensory processing -- having the 'volume of the world' turned up unusually high or turned down unusually low. Ultimately... I think it's illogical to expect others' non-logical parts to operate the same as our own!