The Brazilian arrived from Vasco da Gama in 2010, but never quite delivered on his promise and was sold to the Reds for £8.5m.
"I honestly don't know why things didn't work out at Inter," he told the Liverpool Echo.
"I always worked the same way and tried to do my best. Sometimes things are just not meant to work.
"Inter for me now belongs in the past. My head is in Liverpool and it's here I want to develop as a player."