When you're writing up your research, it's a good idea to keep in mind that a lot of the potential readers of your exciting new paper are going to be busy people. I'm not talking about journal editors and referees - they're busy too, but they have an obligation to read your paper carefully.
The rest of us have no such obligation, so you have to convince us that your research results are as interesting and important to us as they are to you.
I read a lot of papers dealing with econometrics and various areas of statistics. I also "pass over" even more papers that come my way via emails, web pages, and the like.
Sometimes I'm following particular researchers/authors because I know from past experience that their work will be of interest to me. Otherwise, the title might catch my eye, and then I'll go as far as reading the abstract, and maybe the concluding section. Depending on the impression I've gained by that stage, I may or may not read the paper itself.
I think that, in this respect, I'm pretty typical of most of my colleagues. So, that's why the abstract of your paper is crucially important.