Software Design Dilemmas: A Survey

Please respond with moments of dilemma around software design. Please be specific (I’ll post one of my own as an example). The dilemma can be a “what?”, like, “How do I design this system?” It can be a “who?”, like, “We need to change the design but who does it because we’re all busy?” It can be a “when?”, like, “We need to change the design so it’s easier to change behavior but we have to make all these behavioral changes first.”