The 39-year-old joined Somerset in October and replaced Marcus Trescothick as County Championship skipper.
"I haven't been particularly happy with my own contributions," Rogers told BBC Radio Bristol.
"Then you start to think about the reasons for that, and Father Time starts to come knocking on the door."
Rogers played 25 Tests for Australia over seven years and made five centuries, retiring from international cricket after the 2015 Ashes series.
Asked how likely he is to return to Somerset next year, he replied: "Probably doubtful, to be honest.
"Everyone has different motivations and the ability to fight hard, I think, is what I've been probably lacking a little bit.
"I'm desperate to do well but sometimes it's just harder than others, and so you've got to think about that.
"But I really enjoy it here and I'd like to think I've made a bit of a difference with the leadership."
Somerset captain and former Australia Test opener Chris Rogers admits he may consider retiring as a player at the end of the season.