As DLL results in a Low jitter so the skew can be minimized when compared with that of the PLL
Reason is in a PLL (Ring Oscillator topology of VCO) for every Cycle there is an Accumulation of the jitter but when compared to a DLL there is an Accumulation but only one Cycle, The Jitter is not added up with the next cycle for DLL but it's getting added up in PLL.