"Ronaldo has an extraordinary path in the national team, where he has been since the Euro 2004, and naturally we would like to have him win a big competition," Bento said.
"I don't think he needs to win a major championship for his potential and his abilities to be recognised, for him to be one of the best of all time," Bento said.
Euro 2012, which starts on June 8, will be a major test for record-breaking Ronaldo, who turned 27 in February and is in the run to regain the FIFA World Player of the Year award after a superb season at Real Madrid.
Bento gave Maradona and Eusebio as examples of why Ronaldo should not be judged merely on the basis of trophies.
"Everyone would say Maradona is still one of the world's all-time best even if he had not won the 1986 World Cup," Bento said.
"Eusebio was only in one set of finals in 1966 and is still recognised as one of the world's best," he told Reuters.
Still, while Eusebio lit up England's 1966 World Cup, where he was the top marksman, critics say Ronaldo still has something to prove at major finals, having scored only once in each of the last big tournaments - Euro 2008 and the World Cups in Germany and South Africa.
Bento was adamant that it was unfair to put all the pressure on one player.
"It makes no sense to think and believe that one player can solve all of a team's problems. I don't think that is possible, I don't think that is humane," the coach told reporters.
Portugal are drawn in the 'group of death' together with Germany, the Netherlands and Denmark for Euro 2012. It is a group which the coach said was probably the hardest one the national team has faced in its last seven consecutive tournaments.
"Looking back since (Euro) 2000, this is the most balanced and strongest group Portugal has faced.
"In theory at least, the two tournament favourites are Spain and Germany, but in practice things don't always work like that," Bento said, reminding that all three of Portugal's group opponents are previous European champions.
The coach wants Portugal to be aggressive, dominate the game and not just show off their trademark passing acumen and above-average technical ability.
"What we want is a team which can dominate all moments of the match. We are often known for our counter-attack ability because of our players' speed and technique, but what we want is to keep the match initiative and get the ball back quickly whilst handling it well," Bento said.
However, he explained that because Portugal no longer boasts traditional playmakers like Rui Costa and Deco, he has had to adapt his tactics.
"We don't have players with the characteristics that Deco and Rui Costa had, we don't have a number 10. We play with a different system these days, a deliberate 4-3-3, instead of the 4-2-3-1 before," Bento said, explaining that Portugal will opt instead for a holding midfielder with two players in the centre, side-by-side, feeding wingers Cristiano Ronaldo and Nani.