The problem of bots engaging with websites for the purpose of fraud is growing rapidly.
Bots look for ways to break your website, to compromise your data, to pollute your analytics, to steal your content and to gather information that might be useful in future attacks.
This can be for financial gains or other reasons such as as information-gathering mechanisms, to facilitate a primary attack, for blackmail, or malware. Losses from cybercrime such as this is estimated by US organisation Cybersecurity Ventures at $190,000 per second.
Bots pollute your understanding of how your website works, or what your real human users are looking at and what they want from you.