The 20-year-old has joined the Eredivisie outfit on a season-long loan deal, claiming that his first-team opportunities at Anfield were slim and that he had outgrown the Reds' second-string side.
"[Coach] Erwin van de Looi told me after my first friendly game in Groningen that he'd like to sign me," the Hungarian told Nemzeti Sport.
"Liverpool sign complete footballers for their first team, it's not impossible but very difficult to get in next to Luis Suarez or Steven Gerrard.
"I outgrew the second team so I'm happy that I signed to Holland and I can show myself in the first team of a first division team. It's important that I can go on with my development here."
Adorjan joined Liverpool's youth setup from MTK Budapest in 2009.