The investment return doesn't necessarily have to be directly financial. It could be simply (for example) that a particular type of computer or software makes y

The investment return doesn't necessarily have to be directly financial. It could be simply (for example) that a particular type of computer or software makes you more productive which means you get more work done and therefor earn more money. This is especially true of computers where platform lock-in is rife and there are high opportunity costs to adopting a particular platform, especially if you plan to develop for it. Buying coca-cola is not really an investment (unless you buy stock in the company of course) since you're spending a small amount of money for a short term good. You buy a computer with the intention of using it for a few years at least and you learn a development stack usually with the intention of using it for even more years.