Why is a pyramid of numbers not always a good example of the flow of energy through a food chain?

A pyramid of numbers can be misleading in representing energy flow because it only counts the number of organisms at each trophic level without accounting for their biomass or energy content. For instance, a few large predators can outweigh many smaller prey, leading to a narrow base in the pyramid that doesn't reflect the actual energy transfer. Additionally, some ecosystems may have a high number of primary producers but low energy availability, further distorting the energy flow representation. Therefore, the pyramid of biomass or energy is often more accurate for illustrating energy flow through a food chain.