When you’re building software, regardless of whether it’s software that will be installed on a computer (think .exe) or hosted in the cloud (think www), it’s generally a good idea to follow some methodology. I say generally, because you could choose to ignore the methodology.

The downside of not following some methodology is that things may take you a bit longer, with likely repetition and rework. This could be a problem when you’re creating software on a budget and within a specified timeframe; but may not be an issue if you are just starting out and teaching yourself to code.