Except for scavengers and their dung-eating creatures, most creatures take aroma as a characteristic food standard, and aroma usually means that food is fresh and has high nutritional content, so animals will choose fragrant ingredients when choosing ingredients.
However, relatively highly decayed foods generally contain more microorganisms and endotoxin transformed by them. Without the strong gastric juice and immune ability of scavengers, the bad effects of eating carrion will make them have diarrhea and even die. So most animals in the universe will avoid smelly ingredients.
If the feces of animals are fragrant, it may make animals unable to distinguish food, leading to death by swallowing too much feces by mistake. Naturally, the feces of some animals are not smelly, but have a sense of fragrance, such as baby pandas, because their absorption ability is very weak, and many detailed bamboo structures can be seen in the feces. Because many nutrients are not completely dissolved, their feces are not only odorless, but also fragrant. Note that this is the feces of healthy baby pandas, and sick baby pandas are likely to excrete smelly feces.
Why is capybara feces so popular with everyone? Why is capybara feces so popular, even if it is not suitable for taking? First of all, there is no direct evidence that other animals like capybara feces very much, but capybara does have the habit of eating its own feces. One of the reasons is that capybara is a herbivore. Green plants contain a variety of chemicals that cannot be digested and absorbed. The absorption capacity of capybara is weak, so that the nutrients in many foods have been metabolized before they are fully digested and absorbed.
This leads to higher nutrients in capybara feces, so capybara sometimes eats its own feces to supplement nutrition. The same is true of dung beetles and other creatures that eat feces. They will get nutrition from feces, and then get unique ecological factors, thus surviving to this day.