There are many stories I could tell with this title. It's such an obvious rule when dealing with electrical devices but so often overlooked as a possibility of the source of a problem when everything else works. Here's my most recent experience that took its toll on more than just myself.
Writing REST applications in Delphi is pretty simple with the advanced components we have available these days. The functionality encapsulated allows us to spend time on the business and user interface aspects of development rather than the nuances of connecting to an API and parsing JSON results. When starting a new REST app, I usually use the REST Debugger that comes in RAD Studio to test out an API before building the app itself. There are other REST API tools but this one has a great feature that saves me time building my Delphi app that no other tool has.
At the top of Delphi's code editor, is a Navigation Toolbar with several "jump lists" as I like to call them. They help you find and jump to places in your code quickly by selecting them from lists built by the parsing engine in Delphi. There are also shortcut keys that allow you to use them without taking your hands off the keyboard to use the mouse.