I heard in a bayan that once a sahabi (and I think it was Hazrat Abdullah bin Mas'ud (RA))asked Prophet SAW to teach him a duaa when he taught him the duaa mentioned above and told further that this is the duaa most liked by Allah SWT. Alhamdulillah this duaa is very comprehensive covering everything, first we ask for forgiveness as sins acts as hindrance in everything and then we ask for aafiyah in the world which includes health, wealth, family and everything related to this world and aafiyah in the akhirat. Allahu alam