Question

Why some plants do not have chloroplast?

Answer 1

Some plants are heterotrophic, like us, and parasitize directly on other plants.
they connect themselves to the roots of other plants with sneaky penetrating roots of their own, then steal all the sugary goodnes. Since they get all their energy from other plants, these heterotrophs result in a plant that doesn’t have chlorophyll (on purpose, not because of chlorosis or “white forms”), doesn’t need the sun, and just pops its little face up to reproduce. they need to live.

Since chlorophyll is needed, chloroplast also doesn't exist in these plants