Just think

In the past few years, several mistakes have been made by the big three.

And I believe you're allowed one mistake in vidjagames life.

A lifeline saves you from that mistake, and I think all three have used theirs. And their is no more.
Thus no more room for mistakes.

Sony used theirs from the PS3 launch. It was rocky, unstable, but they came back.
Hell, they had two lifelines because somehow they came out of the inFamous 2011 hack stronger.

Microsoft are using theirs now. So far they've been relatively successful. But they made a huge mistake with the launch of xbox one.
So much so don mattrick held his head in shame (Notice how I dont capitalise the devils name (only joking business aside DM is actually kinda a nice guy)
And they've used their lifeline to get out of the mess that they made. They're doing ok now, when they were destined to flop.

Nintendo used their lifeline on 3ds. It wasnt doing well (compared to print-money-ds). They used it on 3ds, and they turned it into a success. If they cant turn wii u into a major success like what ps4 and the bone are heading to, then we know they're out, and their last hope of success remains with handheld(?) and there's no lifeline left!

What you think? 
Also ioi pls upd8 qikr

You're leaving out too many blunders. By now all 3 have probably used up at least 9 lives.

Nintendo has a lot of 1-UP.

Nintendo is here to stay 125 years and countin and people make many mistakes in life thats life

Nintendo pumps out mistakes like it's their primary export. I'm sure they've averaged at least one blunder per year since entering the industry.

I mean, they didn't use up their lifeline on the Virtual Boy?

hey now, don't talk crap about Virtual Boy, it was and still is OP ;)
You know you want one

Correct, about 7 billion of them last time i heared.

Now, this is just my opinion, but I do not see Nintendo competing against Sony or Microsoft, heck, I am sure even Nintendo does not see themselves bringing an even fight to those two, what Nintendo is all about is making profit on their consoles regardless how much the other 2 make/spend. Now I totally see people comparing consoles after all they are video game systems. Now Mario Kart showed it doesnt take much to make Wii U a profitable console, if Ninty could just find a way where the Wii U is pushing an avergae 70-80k a week it should be more than fine. Remember Nintendo makes the double amont on one copy of their games sold than let's say Activision makes on an COD game.

Microsoft used their lifeline with the RROD way back. Just like Sony used theirs on the PS3 launch. They were both very fortunate last gen that they both stumbled so majorly.

Nintendo has Immunity. It has been around for 125 years and counting. They're unlike any other. Sony and MS's gaming divisions won't be going anywhere either. Sit back and quit thinking mobile should compete with console. They're totally different fields.