Short answer
Lower-chest suppression eased so the jacket follows the rib line.
Why it happens
Ribcage width below the chest measure.
Why ready-to-wear cannot fix it
Size charts grade uniformly; wide ribcage is a personal geometry. A block adjusted in one place pulls in another — which is why the correction must exist in the pattern, not in the fitting-room mirror.
How the house drafts for it
Lower-chest suppression eased so the jacket follows the rib line. The correction is recorded in your Fit Passport, so every later commission starts from it automatically.
Where it matters most
This correction carries most for: suit, blazer. It is reviewed at every fitting, in every city, for every garment.
Fit Library entry 26 of 48 · Reviewed by Bonturberg Editorial Review · 2026-09-08