Why do i get less traffic even if my website ranks for a keyword

Yeah this is a great point Phil_T although you've spent time doing your keyword research and ranking okay in position #3 and #5 on Page 1 - are your Titles and Description 'call to action' does it make them want to click?? Its good to do a bit or research on how to successfully create those Google excerpts and title headings.....might be worth looking into, just taking a guess that could be an issue perhaps?? Cheers