Perth combines three things that punish exterior paint: very high UV, long dry summers with big daily temperature swings and, across much of the metro, salt air off the coast.
The signs are always the same. North and west walls fade years before the south side. Render cracks finely from repeated heat cycles. Fascia and gutters chalk, and aluminium frames oxidise to a dull white bloom. Meanwhile the sheltered south wall still looks new, so repaints get delayed.
You cannot avoid this, but you can specify for it: UV-stable pigments, a flexible membrane that moves with the wall, and salt-rated primers on coastal jobs.