Some people stay in a state of what they think is ease and comfort when in actual fact they might not be happy and if they just had the courage to change their situation they could be.
But I see what you mean - its not that clear a quote!
who's to know if they're happy better than they know it themselves? The people who do appear to sacrifice comfort - marathon runners, for instance - actually do it because running makes them feel better than sitting in an armchair; so in a way they are seeking comfort, not sacrificing it.