Anchor tapes are a little different. While you obviously have to show good communication skills and a personality that fits the story you're reading, you may be unwittingly making a mistake that sends up a red flag.
If you're wearing more than two different outfits on a tape, a News Director is going to wonder whether you can make it through a single show without stumbling.
Many anchor tapes are a collection of clips from the desk; a welcome and a lead story, some stuff from the A & B blocks, a consumer or health lead-in, a kicker. Then some cross talk with weather and sports. But if every clip is from a different newscast, it's a subtle hint that you can't muster all your best work in a single day.
It's best to pick one, or at most two, of your best newscasts. Show that you can hit a home run on any given day, because chances are if you get a call, a News Director is going to ask you for a second tape of your most recent anchoring.