Most random people who knock on the door politely introduce themselves when you open the door.
For example "Hello, I'm Derick from Unicef and I'm looking for donations blah blah blah"
Now annoying as it may be for some at least he had the courtesy to introduce himself.
Why don't JW's do this? Is it because they are embarressed or perhaps they know you won't take their literature if they do?
I find this slightly rude and deceiving, especially coming from people who are supossed to be fine examples of 'good christian folk'.
The only company I know of that doesn't always introduce themselves first at the door is Safestyle and anyone who has used them will probably understand why.