Maybe I'm the only one, but it bugs me when I get meat or cheese from a deli, and it isn't sliced how I wanted. I say "thin", or even "very thin", and they hold up a piece of cheese for me to see. When they're standing at least 10 feet away, I have trouble actually seeing how thickly or thinly it's sliced.
Here's a remedy for coming home to too-thin or too-thick deli meats and cheeses.
Most (all?) of the commercial deli slicers have a numbered dial for measuring thickness. For example, a setting of "5" might be the general "thin", a "10" might be the general "medium", and a "15" might be "thick".
When the deli worker hands you a little baggie of perfectly-sliced meat or cheese (the exact thickness you always want your cheese, for example!), ask what number the slicer was set to for it. Then write it down (or just remember it, if you have a good memory).
The next time you order some cheese, you can say, "Please slice it on number 3" or whatever number was perfect for you. That way, there's no guessing, and you never end up buying meat or cheese that's too thick or too thin.
Before we were married, I worked in a deli, and I actually loved it when customers told me a number for slicing. That way I knew I was doing it exactly how they wanted!
Perfectly sliced deli meats and cheeses. That's what works for me! :)