The struggle makes the victory sweeter and losses harder to bear. Whichever you get from life, at some point, you will still get depressed. The human body is at its peak when it finds use for its abilities, when it is able to function.
For example, when you accomplish something creative, you continue to do it with a smile on your face. Because you know your abilities are still lower than the par average, you end up trying again and again until you attain your goal of making a good quality work. Your body is happy because it accomplishes something. Your mental capacity is narrowed to a manageable point that relieves you of other things you think about and you single out this one fine moment.
The same is true with achievements and losses. In physical terms, this is the climax of your personal activities. Once you attain your goal, you have climaxed your body’s function, and you have seen the results in its physical form. The feeling of satisfaction is endorphins rushing through your body, and the tension from the fight-or-flight body mechanism leaving your body.
This is how our body functions. So in the end, it’s not about whether you won or lose, but rather, if you are still functioning or losing sense in your personal use.