If you choose only keyword for the development of your website that will be a biggest blunder from your side because the competition level with single keyword is much high and very difficult to achieve. In order to get proper success you need to improve your website by putting relevant content in the website. This is a difficult task to include fresh content every time. In order to get the real improvement you need to choose popular keywords for your website. What is your opinion about these things? You can put your comments in this context.