Why are weeds and wild plants not affected by insects and pests?

Explanation

1) Weeds and wild plants produce waste products which are stored in leaves, bark and fruits.
2) Several compounds are synthesized by weeds and wild plants for their own use especially for defence.
3) Several weed and wild plants prepare chemicals and store them in different parts for protection against herbivores, insects and pests.
4) Most of these chemicals are unpleasant to taste and hence insects and pests do not prefer to eat such plants.
5) Some of the chemicals are toxic and may even kill the insects and perts that eat them.
6) Hence weeds and wild plants are not affected by insects and pests.