Question

why does Hibiscus does not bear fruits even though androecium and gynoecium present in it​

Answer 1

See there are different type of strategy a plant adopt to propegate themselves. Hibiscus as you know they grow their Adventist roots very fast that help them to grow fast. Thats why they have reduced seed formation. Ok find the relation you know Roses can grow by cuttings so they generally no grow by seeds. Lemon, Orange and many other plants those can grow by cuttings generally not produce seeds well.

or

There is pollination in hibiscus. But the pollen cannot germinate. If pollen is germinate the pollen tube cannot reach to the egg cell to fertilize it. It is called as pollen incompatibility and it occur due to the different biochemical products produced by the biological activity THOUGH the pollen incompatibility is mostly due to genetic reasons, it can solved by artificial method Thus it can produced artificial hybrid Verieties.

Answer 2

$\huge\mathfrak{Answer:-}$

Hibiscus does not bears fruits even though androecium and gynoecium present in it because the fruit seeds will not be similar to the parent plant and look different.

When the pods of this plant fully mature, a crack is formed which opens up and throws out the seeds, which does not allow the hibiscus plant to bear fruits.