What makes a great guitarist?

I was asked this question a few weeks ago and at the time I can honestly say I was slightly stumped by it. There are so many factors that contribute to making a guitarist great as opposed to just an average player. Of course its a personal opinion on who we consider to be great but I guess for this question we can simply look at the universally considered guitar greats and apply the 5 main areas I feel all apply to the greats. 

1.) Tone - For me a guitar great can instantly be recognised on a track by their unique individual tone of their guitar. I personally like a guitar tone that sings in the track almost at a vocal level, nothing too harsh or full of crazy effects. For me the tone master is Eric Johnson, he has a wide pallet of varied tones that he will blend together throughout his music.

2.) Technique- A guitar great simply has to have great technique, doesn't necessarily have to be the worlds most technical or speediest of players. Technique is about having the instrument under control at all times and being able to make those simple notes shine through, getting a perfect blend of tone and technique. Of some of the greats are faster players but again they have the control over the speed and will blend it with those perfectly played slower sections.

3.) Personal phrasing- All of the great players can be recognised by the way that they play their lines and phrase certain solo ideas. An example for me has the way that some players like to jump around the guitar from high to low sections, where as someone like Slash will for the most part play an ascending climb to build up to the higher notes on the guitar. I can always tell who the guitarist is in tracks where there maybe multiple players taking solo breaks by the way that they play certain lines and ideas, mix that in with their individual tones and you start to build up the package of what makes a great guitarist. 

4.) Song writing- Most of the great players are not just great at ripping out solos and lead breaks but also at writing great songs that stand strong for years. Songs that may inspire people to play guitar or in fact start writing and forming bands of their own. Using Slash as my example kids today are still loving the old GnR tracks that came out in the 80s, proving that the song writing is strong and the songs will stand for many years to come.  

5.) Identity- All of the great player have a personal identity that always shines through in the way that they play and sound on the guitar. It maybe something as simple as a top hat for Slash or Steve Vai's large fan that he uses at the front of the stage to blow his hair around, or perhaps its a full outfit such as Angus Young's school boy outfit that he has so famous for. This own personal identity has help them be instantly recognised as an individual player amongst their fellow band mates.
I believe if you put all 5 of these aspects together that you start to build up a good base for what can make a great guitar player. Not all players have these and are still great guitarist but from my own favourite players I find they all have these aspects in common.