ShipScript has been an eBay Community volunteer since 2003, specializing in HTML, CSS, Scripts, Photos, Active Content, Technical Solutions, and online Seller Tools.
I'm going to say, "Proofread your ads." 
This (below) just popped up in mobile format on my smartphone. Someone's getting a bit muddled up with their double letters. It reminds me of the time that the label printing page managed to misspell the word "Successful" in honking big type across the top.
If they put that much thought into acronyms I don't think they would have called one of their programs Guaranteed Delivery. 
Schooled well as a child, entering the workforce began my immersion in a "second language" that was truly my downfall. No one around me spoke proper English and my ear became accustomed to the colloquialisms.
After several decades of written communications with foreigners, I tend to gloss over the missteps in language usage. But I do still mind the mistakes that I see everywhere on official eBay pages. 
My own biggest problem now is that I'm a typist, and when typing my thoughts, my mind thinks one word and my fingers type some other word. Usually it's a homonym, but sometimes it can be an entirely different word (like that buyer/seller thing). Yikes!! Or sometimes a word just fails to appear. 
Anyway, I've given up trying to be correct on the forums. I don't have the fortitude at this age to worry about petty mistakes. I punctuate where it looks pretty, and let my fingers have the last word on occasion.
However, I still hate to hear "momentarily" on flights. I do not want to be lifting off "momentarily" -- once off the ground, I'd like the plane to stay up there! 
And when calling various support lines, I don't want someone to be with me momentarily. I would like that person to stay with me and solve the problem, although "momentarily" is usually what I get while being passed along to the next rep.
