Villas-Boas helped to build his reputation in the competition, winning the trophy during an unbeaten season in charge of Porto in 2010-11.
The Portuguese coach thinks that the tournament should be treated with more respect by the Premier League.
He said: "The profile of the competition is raised in other countries, but not England. I don't understand it.
"I'm also not in a position to criticise others managers' approach to the competition.
"I respect the competition. I certainly think it is viewed as a punishment in England and I cannot understand why. It is a traditional trophy."
Spurs continue their participation in this year's Europa League with a trip to face Panathinaikos in Group J on Thursday.