Every time this question comes up, someone inevitably brought up the plug cycles (5000 vs 10000). My experience proves otherwise. I have used USB Mini since released (Circa 2000 'til now) and have experienced only 1 bad USB connector, and that was due to me rolling my office chair over it.
I recently switched to USB Micro just because you can't get a phone with anything other than USB Micro, and within 3 months, the connectors on 3 out of 5 chargers have connectivity issues. The remaining 2 work under the "if bend it, then it works": http://www.youtube.com/watch?v=E0Dzp5l2PyY
None of the chargers fit snuggly into socket. The connectors are flimsy and get damaged easily. Just rolling up the charger and putting it in my pocket can cause the tip to break off.
So to summarize my data:
- in 10 years, 1 USB Mini out of many have connectivity issue (due to being run over by a chair)
- in 3 months, 3 out of 5 USB Micros fail and the remaining 2 are defective.
Of course, I am just one person, so N=1 may mean that I am a statistical anomaly. However, I would like to see the consortium's real world usage data.
The bottom line is nobody cares about # plugs 'til failure in laboratory situations. What the consumers care about is: how long will it last? It is quite possible that the USB Micro can withstand more plugs in laboratory environments, but in the real world, these chargers get rolled up, placed in pockets, thrown around, etc. I guess engineers sometimes forget this. Too hard, won't do it, so ignore it.
Briefly Googling for USB Micro failure vs USB Mini failure suggests that I may not be alone in this.
With respect to the "USB Micro is smaller" argument, they are the same width and only 1.2mm smaller in thickness. The average cell phone thickness is about 13-15mm. 1.2mm represents < 10% of the phone thickness, so I would argue 10% in thickness is a small price to pay for the durability improvement.
The nuisance in this is that I now have many USB Mini chargers sitting around that I have accumulated from devices in the past, and I am at a shortage for USB Micro chargers.
While cables and chargers cost close to nothing to make, they are > $10 to purchase. We know that in the industry, the profit margin for cables are very high.
Conspiracy theories aside. I would speculate that part of the move is economically motivated.
"People no longer buy chargers because they last too long. Let's come up with a new standard that don't, and come up with some BS to explain it."