
Why this situation was happen in Malaysia???

3R- reduce,reuse,recycle
Landslides are caused when the stability of a slope changes from a stable to an unstable condition. A change in the stability of a slope can be caused by a number of factors, acting together or alone.
Natural causes:
- Groundwater pressure acting to destabilize the slope
- Loss or absence of vertical vegetative structure, soil nutrients, and soil structure.
erosion of the toe of a slope by rivers or ocean waves
- weakening of a slope through saturation by snowmelt, glaciers melting, or heavy rains
earthquakes adding loads to barely-stable slopes
- earthquake-caused liquefaction destabilizing slopes (see Hope Slide)
volcanic eruptions
Human causes:
- vibrations from machinery or traffic
blasting
- earthwork which alters the shape of a slope, or which imposes new loads on an existing slope
- in shallow soils, the removal of deep-rooted vegetation that binds colluvium to bedrock
- Construction, agricultural, or forestry activities which change the amount of water which infiltrates into the soil.