Simply put; AT&T (among others) are eager for competition notably with Verizon and are desperate to get a 2 letter word to "impress" there customers. Basically AT&T is like "oh its 8 inches alright

" while Verizon is like "No stop lying to yourself". If you don't get the comparison please don't ask that's borderline inapropriate but I think it gets the idea across. AT&T should stop wasting there time trying to make something bigger than it actually is.
AT&T is rather like "DUDE, IT'S BLACK(resp. 4G)!!!!1111", and Verizon tells them "Well, but you're 10 years old, though(resp. HSPA+ might be 4G, but not at 14.4MBit/s. Roll out 42MBit/s, then 84MBit/s, then actually sell phones that support that data rate and THEN you might call it 4G)".
Even Sprint's 4G WiMAX (10MBit/s) and Verizons 4G LTE (
5-12MBit/s) networks aren't 4G.
IMT-Advanced said:
Peak data rates of up to approximately 100 Mbit/s for high mobility such as mobile access and up to approximately 1 Gbit/s for low mobility such as nomadic/local wireless access, according to the ITU requirements.
84MBit/s should count as "approximately 100MBit/s".
How about just calling it 14.4MBit/s HSPA+, AT&T? 10MBit/s WiMAX, Sprint? 12MBit/s LTE, Verizon? That would quite suck, huh?
Besides, in areas where DSL tops out at 2MBit/s and cable is not available, 7.2MBit/s over the air is already not too shabby. Just roll out 21.2MBit/s for the iPhone 5, 48MBit/s for the iPhone 5S, etc., and some day - magically - there will be 4G speeds - even though this would be 8G or something like that according to the carriers.
4G with 1GB data cap is still just that, though - blown through in a matter of minutes, and afterwards you're left with good ol' 2(.5

)G EDGE speed.