Practicing guitar for 10 hours a day is physically impossible.

Yes, you can practice MUSIC for 10 hours a day, and spend about 2 or maybe even 3 hours specifically focusing on technique...

But the rest of your time would be spent practicing other things, like memorizing the fretboard, training your ear, writing songs, improvising, etc.

If you spend more than 2 or 3 hours a day on technique, you will injure yourself.

That being said, I've spent a whole month where I practiced music for 16 hours a day. But technique was only a very small part of all that...

Hope this helps! :D