Because recounts get ugly and ballots tend to "go missing" between the real vote and the recount once partisans get their mitts on them.

Why no recount in states Hillary won if all they want to do is verify the results?  After all she won New Hampshire with a much smaller margin than Trump won these states they are recounting.  Why no recount there?

Lets stop pretending that this is an attempt to verify that the election was clean.