People in our industry think they stopped doing waterfall and switched to agile. In reality they just switched to high-frequency waterfall.
Code reuse sounds great but is difficult to achieve. Make the code too specific and you can’t reuse it. Make it too general and it can be too difficult to use in the first place.
Did you ever wonder why most solutions to program glitches are fixed by rebooting your computer or restarting the offending application? That’s because of state. The program has corrupted its state.