Malthus model does not consider the influence of external factors on population growth, and thinks that population growth rate is a time constant. When the population is small, the model may make a more accurate prediction of population development, but when the population base is large, the model is not valid.

Logistic model is a population blocking model, and the influence of environmental factors on population growth should be considered. As the population increases, the population growth rate will decrease. Therefore, this model can still make a more accurate prediction of population growth when the population base is very large.

Because the inventor of this model is a biological expert, he went out for some time because of something while doing the experiment. According to the growth rate of bacteria, his laboratory will be full of bacteria. But when I went back, I found that there were not so many bacteria, because the nutrition in the culture container was limited and the growth rate of bacteria was limited by the environment. So he improved Malthus model and put forward Logistic model. I think your teacher also mentioned that this model can also be used to predict the publicity effect of bacteria, fish schools and even advertisements.