Are you asking why Cathay painted it? Cathay painted that aircraft in that paint scheme back in the mid 90s (1994?) when they adopted their new and present livery. Originally, they had not plans to get rid of their 742s and 743s, but when the Asian markets crashed in the late 90s, Cathay decided to retire their older 747s to cut capacity. I know that the 742s (except freighters) were scheduled to go first, but I think that they were contemplating holding onto the -300s for a bit. Eventually, they decided to dispose of both the -200s and the -300s (again, except for some freighters). In fact, most of the -300s are now seen regularly operating for PIA (did one or two go to Air Atlanta?) So, they did not plan on disposing of that aircraft when they chose to paint it that way. However, with how the industry works, you have sudden changes all the time.
They have painted a -400 in a revised scheme though, and I think that it looks great!