Mileage Run Discussion - ITA vs. commercial software?

I have been practicing with ITA lately and find I can often find a cheaper flight using Orbitz or Expedia. Am I doing something wrong? Thanks.

I have been practicing with ITA lately and find I can often find a cheaper flight using Orbitz or Expedia. Am I doing something wrong? Thanks.

I was under the impression that ITA is what Orbitz uses.
Expedia sometimes does knock off a few $ I found for complicated routings