There were three guys named Jackson who were all in the clothing business.
Due to lack of real estate options in their city, they all set up shop next door to each other. In order to convince customers to come to their store rather than one of the other Jacksons, they all put up signs to attract customers.
The one on the left puts up a sign that says "Jackson's clothing store (BEST PRICES!)"
Not to be outdone, the one on the right puts up a sign that says "Jackson's clothing store (BEST QUALITY!)
The one in the middle thinks about it for a while, and eventually puts up a sign of his own.
"Jackson's clothing store (MAIN ENTRANCE)."