More likely, it's because I have a tendency to ramble and get off the point of the conversation. And that's what The Bottom Line is. It is the main point that you're trying to get across. If we were talking about essays or papers for school, we'd be talking about our conclusion.
When you're getting lost in all the complicated and confusing details, you can say, "But the bottom line is..." Or is someone is getting frustrated with me, they may say, "That's all fine, but what is the bottom line?"
There are actually quite a few idioms that address this. That might be an American thing. We want to do everything so quickly and immediately that we don't want to be bothered with the details. We just want the main point.
Thanks for coming with me through another week of idioms. Have a great weekend, and I'll see you next week!