Particularly if you relocated.

Had that happen to a co-worker once. He moved (on his own dime) from Chicago down to Dallas, then got let go just three months later. He wasn't even bad, he just wasn't performing at the level I guess they wanted him to. I never imagined back when I was in school that programming, of all professions, would be as cut-throat as it is.

That only matters if you think it's possible for the people doing the hiring to be fallible, which...is not a given in this industry.