What are the disadvantages of a pie chart?

Pie charts can be misleading when representing complex data sets, as they often oversimplify the information and make it difficult to compare differences in size among slices, especially when they are similar in size. Additionally, they can become cluttered and hard to read if there are too many categories. Lastly, pie charts do not effectively convey changes over time or trends, making them less suitable for certain types of data analysis.