How often do you get mixes when they should be pure?

[shortcake1806]

I've ordered about two dozen different shipments of eggs this spring. Out of those I've had three occasions that I hatched out obvious mixes from what should have been purebreed eggs. Does this happen to anyone else or is it just my rotten luck?

 

[peckndirt]

It happens but not that often.Only happened to me once and I sent 2 Buff Cochin eggs with some Barred Rocks once by mistake but never a mixed chick unless they wanted one.