The Brazil midfielder left Lazio for San Siro on the final day of the January transfer window in a €20 million (£16.5m) move, leading to furious supporter protests against Lazio president Claudio Lotito.
Hernanes, however, has stressed it was his decision to leave the club as he aims to fight for the Serie A title and play in the Champions League.
"I want to clarify that no-one forced me to say anything," he told GoldTV. "I chose to go away and it was not a question of money.
"After a fantastic three-and-a-half years, where I was always treated with dignity by Lotito and [sporting director Igli] Tare, I realised that if I wanted to play in the Champions League or win the Scudetto, I had to try something new.
"With Lazio, me and my team-mates were not able to reach certain goals. So, as soon as the opportunity came, I took it.
"I thought about, when Inter came in for me, and I made my decision. Again, after three-and-a-half years, I realised I would not have been able to achieve my dreams with Lazio.
"Inter made me an offer. This is a team that has a name, a higher outlook where maybe I can achieve my goals. It is not a question of money."
Hernanes joined Lazio from Sao Paulo in August 2010 and helped them win the Coppa Italia last season.
The 28-year-old could make his debut for Inter against Sassuolo on Sunday.