Did you know that Google, and probably the other search engines, uses your web history (where you’ve been & what you’ve searched for) to tailor the results you see when you search.
That’s fine and probably useful for the general public, but for someone like me who is constantly checking where clients rank for particular terms, or for my clients who do that themselves, we don’t want “tailored” searches. We want as much of the unvarnished truth of rankings as we can get.
This page tells you how to make Google not do that any more:
I can think of times when it might be useful to let Google deliver more personalized results, but I think in general, I’d rather they not. I had noticed a while back that if I searched for something and my location in Google was shown as Austin, I would get slightly different results if I changed my location to Chicago. Makes it kind of tricky to do SEO for a company with clients all over the US, much less the world!