I don't know that there's anything you did wrong or that you can do about it, but what you've got there is called "pilling". See the link below for an explanation of why it happens.

Here is a link that might be useful: Wikipedia.org: Pill (textile)

Are they new shirts, or ones that have been worn for a while? If they are new, take them back to the store. If you have had them for a while, either live with them or discard them and buy shirts that have no polyester in them.

" I didn't do the warm iron which I have no idea what it was talking about."
That means to use a WARM iron setting, if you need to iron out any wrinkles before wearing. A higher iron setting could cause the polyester fibers to melt, and will definitely cause out-gassing.

Be sure to turn the garment inside-out before washing & drying. Any type of polyester (synthetic) blend fabric will be prone to pilling.

I've noticed more abrasion/mini-pilling on my 100% cotton knits after buying a front-load washing machine. Less water = more friction.

With those, I now use the Delicates cycle because more water is in the drum, which reduces the friction. I also wash those as smaller loads, to maximize the buffering effect of the higher water level.

Here is a link that might be useful: try this link

This post was edited by Cavimum on Fri, Aug 15, 14 at 8:58