That is true for most cases, which nowadays is web and backend software. As you get into embedded or anything involving hardware things get slower and you need

That is true for most cases, which nowadays is web and backend software. As you get into embedded or anything involving hardware things get slower and you need to optimize. For example, tests involving read hardware can only run at 1x speed, so you will want to avoid running those if you can. If you are building a custom compiler toolchain, that is slow and you will want to skip it if the changes cannot possibly affect the toolchain.