Why would you take trees only from the canopy layer?

Question

Quizplus · Accepted Answer

Harvesting trees from the canopy layer can create gaps that allow more sunlight to reach the lower layers, which can help stimulate growth and promote greater biodiversity. Trees in the emergent layer are typically too tall and difficult to harvest safely, so they are generally left alone. The value of trees in different layers can vary depending on the species, size, and location, so it is difficult to say whether the canopy layer is always more valuable than the other layers.

Why Would You Take Trees Only from the Canopy Layer