There are several reasons why there may be a large number of invalid local business listings online. One reason could be that businesses may have closed or moved, but their information has not been updated on the website or directory where the listing appears. Another reason could be that the listing was created by a third party without the business’s knowledge or consent, and the information may be inaccurate or out-of-date. Additionally, some businesses may be listed multiple times with different or conflicting information, which can also contribute to the problem of invalid listings.