Jokes about the Internet being a series of tubes aside, I do draw an analogy between plumbing and search engine optimisation.
I am often asked if I can guarantee someone a place on the first page of Google, or the number one spot. Naturally I can’t, because precisely what Google (or Bing or Yahoo!) are going to do is outside my control.
What I can do is make sure your website is up to date with current SEO best practice. Everything will be in place to optimise your site for their indexing.
This is where the analogy comes in. A plumber can make sure your house is 100% ready for water to flow to all the places it needs to. But they should never guarantee that the local water board will never have a supply problem at their end.
If anyone ever guarantees you a position on a search engine ranking, please keep them away from your digital stop cock.