Far from being something that should be repressed, desire is a critical part of happiness. Happiness requires both something that helps you and something that you desire.
Benefit alone is insufficient for happiness. You can have what benefits you and still be miserable if you do not recognize or value that benefit. No matter how good something is, it will not give you joy unless you want it. We can’t be happy without desire any more than a child can rejoice in eating kale due only to its nutritional value. If a child doesn’t want kale, it doesn’t matter how healthy it is, it will not be something that gives them joy. What improves will only bring you happiness when you want improvement.
While desire is essential to joy, it is also insufficient in and of itself to provide you joy. What is desired must also actually provide objective value to you—it must help you. You can be miserable with exactly what you want if it doesn’t benefit you. For reference, see the misery common among the rich and famous. The end of misplaced desire is misery.