Ben
Wait until you are competing with bootleg copies of what you sell from a country with no laws and little to no enforcement to protect intellectual property rights.
Wait until you are competing against new Sellers whose enjoyment is selling, collecting your money and not shipping and there is no local authorities to enforce any laws that may be on their books to discourage that type of activity.
Wait until there are 7 million more Sellers selling your same items for 1/4 of what you are selling them for because their eBay fees are less, their cost of living is less so they dont need to generate the same profit margins to survive on eBay, their source of products is immediate and identical to your products except cost them a fraction of your cost.
Wait until domestic confidence in eBay being a safe trading place totally erodes, and as Jeff puts it, dont forget to turn out the lights on your way out.
Fear mongering? Nope, been there, done that, long before eBay ever existed with over 25 years in International markets selling and purchasing into the millions of dollars.
Malcolm