I've heard speakers that you can pick up and move around and all the while the soundstage is perfectly focused. Not all speakers do that but some do.
The first time I head that Mike Maloney was moving his Tesla loudspeakers around while I was in the listening chair during a dealer demo. The soundstage was very focused on that speaker.
Since a set of our early amps was playing at the time, must be that we got that focus thing several decades ago.
Bottom line - even with perfect bolted down loudspeakers with good
coherency they cannot project a stable image due to the dynamic
modulation of the velocity fed to the speakers by an unstable amplifier.
It must be that its all in the setup. I've yet to hear a functioning amplifier than can't project a stable image.