There is an old saying, "Measure twice, and cut once". This saying came about as a best practice to not waste building materials. If you were going to cut a board down to size, you'd measure the board twice before cutting it to ensure you cut the board to the correct size.

In this fast-paced world of software development, everybody is into the agile way of building out code, which means that a service evolves over several iterations. There is nothing wrong with this at all, except if you don't have a roadmap in mind, sooner or later, you'll have a kitchen-sink-style service that is hard to use, hard to test, and even harder to maintain.

So, you need to follow the "Measure twice, and cut once" motto when building your services, and you need to design them in such a way that they are easy to use, easy to test, and easy to maintain.