Dembele, who joined the club from Borussia Dortmund for 105 million euros ($125.22 million) in the close season, was diagnosed on Sunday with a hamstring rupture which Barcelona said will sideline him until around Christmas.
"What's clear is that this is a player who has never had a muscular problem, he doesn't have the experience to recognise the little pains," Valverde told a news conference on Monday.
"A player at that speed that makes this backheel move getting hurt, it's not normal but it's one of the possibilities. A veteran player might not have done that."
Dembele is in Finland to have his hamstring operated on and Valverde hopes the youngster can cope with being sidelined.
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"It's the hardest thing for a player, he's injured and can't help. He has to be very patient, it's what he has to do," said the Barcelona coach.
"It's just one more problem he will encounter in his career. You never want it to happen but we've all had muscle problems, knee injuries. You have to look at it from a long-term perspective."
League leaders Barca face Eibar on Tuesday at the Camp Nou and Valverde said any one of Gerard Deulofeu, Aleix Vidal, Denis Suarez or Andre Gomes might be chosen to replace Dembele.
While the winger's absence might not be felt for this game, Dembele is also set to miss the rest of Barcelona's Champions League group fixtures and crucial domestic league clashes with Atletico Madrid and Real Madrid.
(Editing by Ken Ferris)
