1. You are talking to a defined target audience
2. You have about 500 words to get your message across
3. You only have about 10 words (The heading) to grab the attention of the reader
4. The reader will scan through the page before deciding whether to read or not
5. Large chunks of text disappoint the reader
6. Strong vocabulary confuses the reader
7. Unwanted links bogs down the reader
8. The copy must have elements like sub headings, bullet points, emphasis etc to make it appealing
9. There is a back button on the browser that takes him/her back to a million websites like yours
10.  There is a close button on the browser that takes him/her away forever in search of better websites
11.  The copy must be different, original and creative.
12.  It must be informative
13.  The tone must be conversational
14.  Personalization is the key
15.  The copy must ‘be’ the reader. Think and talk like him. Connect!
16.  You need to ensure that the copy is loved by search engine bots too
17.  Choosing the right keywords is crucial.
18.  Keyword density is crucial
19.  Keyword positioning is crucial
20.  It’s easy to get carried away and over optimize
21.  It is difficult to strike the right balance between optimization and readability 

Do you have anymore suggestions or points that I may have missed out on? Add it here. Cheers!