Unappreciated meaning

Unappreciated, poor and neglected, it was not until after years of struggle that they attained recognition and success.

As far as is known, Borneo never formed a political unity, and even its geographical unity as an island is a fact unappreciated by the vast majority of its native inhabitants.

Maybe his mood had more to do with feeling unappreciated.

At that moment his home life, jokes with Petya, talks with Sonya, duets with Natasha, piquet with his father, and even his comfortable bed in the house on the Povarskaya rose before him with such vividness, clearness, and charm that it seemed as if it were all a lost and unappreciated bliss, long past.

Vasilopoulos, S., et al. "The small-caliber esophagus: an unappreciated cause of dysphagia for solids in patients with eosinophilic esophagitis."