What are the potential pitfalls of using regex in PHP for text manipulation?

One potential pitfall of using regex in PHP for text manipulation is that it can be complex and difficult to read and maintain, especially for those unfamiliar with regex syntax. To solve this issue, it is recommended to break down complex regex patterns into smaller, more manageable parts and use comments to explain the purpose of each part.

// Example of breaking down a complex regex pattern into smaller parts with comments

$pattern = '/^([a-z0-9_\.-]+)@([0-9a-z\.-]+)\.([a-z\.]{2,6})$/';