The first time I encountered an application with a strong architecture it was a bit of a shock to my system. It slowed down my development since I had to solve the problem in the manner that would fit the architecture rather than however I felt like (which had been my previous experience). Once I was familiar with the system my productivity was restored (other than the crazy manual version control process) and the fact that the system had three sub architectures depending upon the module that you were working in.
The purpose of software architecture is to make an application seem as if it has a single consistent author and design. This speeds future development as a new developer (or user) only has to be shown one part of the system and the rest should behave (where possible) in the same manner.
The opposite of this is where an application has no architecture and each screen could have been written by a different developer with no reference to their co-workers. This makes enhancements more difficult as you need to work out the what and how of the screen/module.
Oh and by the way architectures are designed, not architected.
Developer Rants 