My odd azalea plants

My two azaleas are crazy beautiful again this year. But why do they never grow. They have been this size ever since I got them years and years ago.
The peach colored one is barely 12" tall. The pink one is maybe 2' tall.

The lone azalea

I moved the two azalea plants from the front yard to the back yard last year in hope they would survive.  They were languishing in the front yard.

They are both alive though only this one bloomed this year.

It may look dramatic in this close-up photo but this single set of blooms looks a bit lonely.

Very pretty color though and the plants are still alive so we are happy.