I simply don't understand why more of these women don't use personal dressmakers more - why on earth would anyone want to risk wearing the same outfit as someone else when they're in the spotlight like they are? The whole point is that they are rarefied. I understand that they need to be relatable but working with dressmakers is not that much more expensive and they would even spotlight the dying textile manufacturing in most countries.
Part of it, and I don't meant to sound snobby, is that most of these ladies come from backgrounds where they wouldn't have grown up with getting clothes made for them which is such a shame because there are so many talented seamstresses still doing amazing work and for a fraction of the cost of these often poorly fitted off the rack clothing.
I doubt budget is a big consideration and a dressmaker would certainly be cheaper than some "designer" things, but these ladies probably go "designer" as they don't have "style" credentials themselves to create their own look with a dressmaker. And in many cases some of them have yet to find a "look" that works for them.
What I don't understand is why Mrs Belgium and Mrs Netherlands, and Mrs Lux patronise designers such as Natan - you see them in a "customised" outfit in the same fabric and similar to one that has already made an appearance on one of the others and in many cases the fabric and shape does nothing for them.
QE11 has the right idea - find a style that works for you, hides flaws, and fits really well. Then go for variations on that theme.