Hobby machinists get into the hobby so they (and me!) can make things that come out of their minds, and also copy things that already exist. Often, that is the preference, and they don't want to buy anything they can reasonably make themselves. As hobbyists, it also helps us to learn by thinking outside the box, trying to come up with a design that uses common materials we might have on hand, or cheap and off the shelf parts or tools to modify for making something useful, often more useful to the maker than a store bought tool or part. There is also the pride of doing the entire project, or the major portion of it, from what is already on hand in the shop, to a design that comes from our minds, which is why many of us hoard all kinds of things that might have possibilities in our shops at some point in time. The focus is on "I want to think it and make it."
Other hobby machinists, not so much. They want to get it done as quickly as possible, and get on to the next thing, and they often order fresh materials and tooling for each project, and work from plans or from copying other's work. The focus is often on "I want this thing, ASAP."
It really depends on how we mentally approach doing things. Neither approach (and there are also always other approaches) is "better", it depends on what works for our situations, desires, and resources. We also often switch gears for certain projects. Some are quick and dirty, others are fussy, thoughtful, and careful. That is why this forum is so interesting, seeing how we approach making and procuring things in so many different ways, many of them potentially useful.