What reasons make it undesirable to create large monolithic systems without architectural patterns?

Creating large monolithic systems without architectural patterns is undesirable for several reasons:

• Support and scalability complexity: Without a clear architecture, the code quickly becomes tangled, making it difficult to make changes and add new features.
• Poor modularity: Components are tightly coupled, which complicates reuse and testing.
• High likelihood of errors: Lack of clear responsibility boundaries leads to errors due to unintentional effects of changes in one part of the system on others.
• Difficulties in teamwork: Without architectural patterns, it's hard to divide responsibilities among developers, reducing efficiency.

Architectural patterns (e.g., MVC, MVVM, Clean Architecture) help structure the code, improving its readability, maintainability, and extensibility.