Welcome to the Q&A Forum

If you haven't done any keyword research, your article still contains keywords - you just don't know what they are. It will make the performance of your content erratic. Even this comment which I am typing now, contains keywords which Google will be picking up on. Google doesn't know what research you have done and all strings of text contain words, which when grouped in certain ways can form keywords You'll just get traffic for slightly bizarre queries every now and then as your work will lack focus. Keyword research is something you do to target your content. It doesn't mean that content can't perform without keyword research, though - but that un-targeted performance may not bring the visitors you would wish for