It means the website has been visited 250,000 times in those few days.
You could read it as "250,000 people have visited the site in just a few days." This is good because normally, you want a lot of people to visit your site, especially if you're selling something.
You may have seen counters at the bottom of some webpages. They usually say something like "Thank you for visiting. 0000349523 visitors so far." If you have a lot of visitors daily, you could likely make some money by giving advertisers a spot on your page.
Then, every time someone visits your page, each advertiser will pay you a small amount because whoever visited your page has seen their ad. Then for each ad you have on there, the amount is multiplied. If you're getting 0.05 cents from one company for every time someone visits your page, and another 0.05 cents from all of the other companies, you could potentially be earning .50 cents per visitor on your page (if you have 10 ads). With a page that gets 250,000 views a day, that could translate to $125,000. I think the amount ad companies are willing to pay web-hosts is a lot smaller (maybe 0.001 cent), but you get what I'm saying, right?
I know I gave a lot of extra information, but I thought you would like to know why counting the hits could be important. Some people may not ever add ads to their site; they just want to see how popular the site is. This is simply a possibility.