Google Search changes DAILY, does your web site keep up?
If you are not making regular changes to your web site;
Adding new copy, images, videos. blog entries --- don't expect Google to keep your top organic ranking, if you even have one.
This is why you need a professional marketing company to TELL you, SHOW you or DO IT FOR you.
Why spend money on paid search when you can develop more compelling content for your own business and web site.