Because that's what Apple TOLD you it did. Half the time it doesn't work like that properly, and the other half the time the little light on it doesn't light-up.
Shrug. Haters gonna hate.
MagSafe has worked flawlessly for me and has saved my several MBPs over the years from clumsy dachshunds and kids, many times. It's a very cool solution to a common issue, and the issue grows worse as the laptops grow thinner and lighter and therefore easier to yank off a table. So count me among those saddened to see a non-MagSafe power connector on today's new Macbook.
The only time I've ever had an issue with the MagSafe connector's light not going on was when lint has gotten onto the contacts. A few pecks with a toothpick has cured that on the rare occasion it's happened. I'm talking perhaps three or four instances over the three Macbook Pros I've had since 2010.
If you're having more persistent problems (and I sure hope your "half the time this and half the time that" is hater-hyperbole), I urge you to go to the Genius Bar and have them figure out what's going on. Your MagSafe adaptor is covered by AppleCare.
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Thinner why. to appease shareholders? to appear innovative? certainly not to make it more funtional
Because consumers like it. Thin-and-light wins.
I can attest to that. I upgraded to the 15" rMBP after toting my trusty 2010 conventional MBP for three years. Now, going back to the 2010 (which runs 24/7 as a server now) is awkward. So thick and heavy by comparison!
Once you go thin-and-light, it's very hard to go back.
And so you might change your tune when you pick up one of the new MacBooks for the first time. I haven't done so yet, but I know a couple people who have, and they say it's just stunningly light, nice to hold, and all-around gotta-have, with its spectacular new display.
Frankly I'm not looking forward to meeting this seductive new machine. I adore my 15" rMBP and use every bit of its compute power, so I'm not really a candidate for the new machine. But gotta say, as a frequent flyer I'm more than a bit envious of the portability of this new machine.