A common problem when discussing the need for methodology, standards, etc. is the differing perspectives of team members. New application modules will be more complex. Analysis often involves are series of evolving prototypes with little associated documentation.
Smaller scope means a moderate amount of less formal documentation is often adequate.
A new application provides good opportunity to do business differently. It is largely unconstrained by the existing business, database or code. Resulting functional specification is thick and detailed. Design Relatively little thought is given to design. Components are added as the prototype evolves.