PK-KAR,
it is very difficult to guess
It may be easier to guess, or better consider for the purpose of debate, that full braking, either auto-brake or manual brake was not applied for at lest some part of the landing roll out.
Re;
if the constant decal
; this is an ambitious assumption.
Deceleration during landing is rarely constant; see
CS 25 Large Aircraft / Amendment 4 pages 2-B-36, 37 - diagrams of anti skid response characteristics. Just because auto-brake is set to a desired deceleration value, does not mean that this value is achieved or maintained; it only a target.
(f) The anti-skid function must be able to reduce braking for a wheel/tyre that is going into a skid, whether the braking level is commanded by the pilot or an auto-brake system if installed. (CS 25 2-D-46)