Wylie
TF
Thats an interesting one for me,the 3x3,In addition to Fekins answer, floor tiles are usually larger format i.e 300x300mm or bigger. With tubbed adhesive, it is possible that the adhesive would not fully dry out at all as the moisture just can not get out.
I had tiles to pull off the next day as they sounded boast, the tub adhesive was still soft
Stephen