Portfolio optimization may be known by another term, such as 'optimal asset allocation' or 'modern portfolio theory.' However, regardless of the name, the concept and goal are the same. You want to build your portfolio to generate the highest possible return while keeping the level of risk you're comfortable with.
This entails putting together a well-balanced portfolio, which implies spreading your money over a variety of assets. Then, in order to achieve your desired risk-reward outcome, you'll balance those assets.
Portfolio optimization should result in a 'efficient portfolio,' as defined by investors. This indicates it's delivering the best potential return within your risk parameters.