Thank you for the opportunity to help you with your question!
Plain and simple, think of developing a database without an ERD as building a house without a building plan. It might be doable because you think that simply laying a brick one over another is enough to build something, however the moment somebody else takes responsibility over the project there is disaster potential.
The result of the software requirements analysis (SRA) usually is a specification. The design helps us turning this specification into a working system. Hence software design includes architectural views, but also low-level component and algorithm implementation issues. Depending on the type, a software design may be platform-independent or platform-specific. There are many aspects to consider in the design of a piece of software. The importance of each should reflect the goals the software is trying to achieve.
Please let me know if you need any clarification. I'm always happy to answer your questions.