I can't set my hopes too high, 'Cause every hello ends with a goodbye.

The speaker expresses guarded optimism rooted in the inevitability of endings: even the most promising beginnings (“hello”) carry the seed of separation (“goodbye”). The line captures a defensive emotional strategy—keeping expectations low to soften future hurt—while also acknowledging a universal truth about relationships, opportunities, and phases of life. Its poignancy comes from the tension between desire (to hope) and experience (that things end), suggesting a cycle of attachment and loss that makes vulnerability feel risky. Read this way, the quote is less cynical than self-protective, revealing how past disappointments can shape present emotional boundaries.