The quality of a t-shirt is assured only by quality of raw materials & processes and not simply by GSM.   In order to give cheaper prices many companies increase the GSM alone and compromise on other parameters like using inferior quality carded/semi combed yarn, dyeing processes with cheaper dyes with no color fastness, steam calendaring instead of compacting , printing with sub standard dyes. And the garments are made by sub contracting to local job work units without any quality inspection or procedure.

As a result of this, the t-shirt looks heavy but it will fail in all other qualities like dyeing fastness, feel, finish, shrinkage control, print quality