A pattern is something you follow, it’s a path, a guide, a direction to take if you’re not sure where to start — follow this pattern and you’ll eventually get there.
A system is a structure, a set of rules and processes that will get you there, that you must follow because if you don’t things will break and the last thing you want is for things to break.
Not everyone wants to follow systems, not everyone can handle the flexibility of patterns.
Design Patterns are one of the greatest coding constructs for any new developer. When I was starting as a little bitty coder, they helped me understand so many things in how to write code and how to change my perception of not just what the physical spaghetti code that I was writing could do but it gave it something more.
Best yet, when you talked to other developers, they weren’t worried about the language you used but immediately understood the patterns at play and how they could benefit from them.
Systems on the other hand, I learned as a DBA, that they must be followed otherwise catastrophes could occur (and did). Systems helped us establish procedures for how we do things, we needed to follow steps, we needed to follow directives and we needed to be precise — we couldn’t pattern it — it wasn’t going to work.
