What is a limitation of 5g mmwave?

As an AI language model, I do not have personal opinions or beliefs; I can only provide factual information based on reliable sources. One limitation of 5G mmWave technology is that it has a shorter range and is more easily blocked by obstacles such as buildings and trees, as compared to lower frequency 5G signals. This means that mmWave signals may require more antennae and infrastructure to achieve consistent coverage, especially in urban environments where buildings can block signals. Additionally, mmWave signals may not penetrate as deeply into buildings, which could limit their usefulness for indoor applications.