Hope, in this deep and powerful sense, is not the same as joy that things are going well, or willingness to invest in enterprises that are obviously headed for early success, but, rather, an ability to work for something because it is good, not just because it stands a chance to succeed. The more unpropitious the situation in which we demonstrate hope, the deeper that hope is. Hope is definitely not the same thing as optimism. It is not the conviction that something will turn out well, but the certainty that something makes sense, regardless of how it turns out.

Václav Havel (1936-2011) Czech playwright, essayist, dissident, politician

Disturbing the Peace: A Conversation with Karel Hvížďala, ch. 5 “The Politics of Hope” (1986) [tr. Wilson (1990)]
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The last two sentences are usually combined as:

Hope is not the conviction that something will turn out well, but the certainty that something makes sense, regardless of how it turns out.

Variant:

Hope is not the conviction that something will turn out well, but the certainty that something is worth doing no matter how it turns out.