打個比喻 你間屋出面道圍欄有一個好細嘅鏽跡 你可以磨佢然後再上漆 但如果你唔理間屋一百年 成個欄就會生鏽到剩返一堆橙色嘅鏽屑
To use an analogy, there is a tiny rust on the fence outside your house, and you can grind it and then paint it, but if you don't care about the house for a hundred years, the whole fence will rust until you are left with a pile of orange rust