In short; to sum up — used to present a conclusion or summary of what has been said.
つまるところ、彼は助けが必要だということだ。
In short, what it means is that he needs help.
つまるところ、その計画は現実的ではない。
In short, the plan is not realistic.
いろいろ議論したが、つまるところ時間が足りなかった。
We discussed many things, but in the end there simply wasn't enough time.