1.  Documentation:
One of the primary purposes of HTML comments is to document your code. They provide clarity and context to anyone (including yourself) who reads or works with the code. Comments help you remember why you wrote a particular piece of code, what it does, and how it fits into the overall structure of the webpage.

2. Debugging:
When troubleshooting issues in your code, comments can be invaluable. By temporarily commenting out sections of your code, you can isolate problems and test different solutions without altering the original code. This makes debugging more efficient and less error-prone.

3. Collaboration:
In collaborative web development projects, comments can facilitate communication among team members. They provide a means to share insights, notes, and instructions related to specific code segments. This enhances teamwork and ensures that everyone is on the same page.

4. Temporary Removal:
Sometimes, you may need to remove a part of your code temporarily. Instead of deleting it and risking losing important code, you can comment it out. This way, you can easily restore it when needed.

5. Accessibility Testing:
Comments can be used to mark sections of the code that require accessibility enhancements or testing. This is especially important for creating websites that are inclusive and usable by people with disabilities.