Interdiffusion in InXGa1-XAs/GaAs quantum dots (QDs) may occur during high temperature growth and processing, which may create problems in the ultimate device performance. It is simulated through successive high temperature annealing, and the changes at each stage are studied through photoluminescence (PL). Significant changes are observed in the peak energy, linewidth, and intensity of the PL spectra. These have been attributed to relaxation of strain, changes in the composition of InXGa1-XAs, and size distribution of the QDs, which fail to establish proper understanding qualitatively and quantitatively. In this Communication we present appropriate interpretations of the changes in the observed PL through quantum mechanical concepts and computations.