Why lysosomes are called the garbage trucks of the cell?

Lysosomes are membrane-bound organelles found in many animal cells. 

Lysosomes are membrane-bound compartments containing hydrolytic enzymes that regulate the intracellular breakdown of macromolecules. Lysosomes serve as the cell's waste disposal mechanism, digesting obsolete or unutilized cytoplasm components from both inside and outside the cell. Endocytosis transports material from the outside of the cell, while autophagy digests material from the inside.

Hence, lysosomes are called garbage trucks of the cell because they remove all unwanted cellular material.