While motion design is open for imagination, architectural design is a profession of precision.
Everything must be created in the precise size, at the precise place, precisely calculated to fit the project that has to be built as such, as shown in the construction engineer's plans.
But even here there are possibilities for 
open minded presentations, especially when it comes to show life in motion.
Nothing is static.
Everything is dynamic.
Here you can see a few examples of motion design integrated into architectural imaging.
It is so much more interesting, when an architectural design comes alive with motion.