I'm no longer deleting comments that are not relevant. From now on, I'm going to keep them and approve them after I edit them to make them relevant.
Dave

I couldn't agree more with you Don't be half arsed when commenting on sites, you are missing out on opportunities.

Totally with you on this, people have to remember that comments of that nature will affect negatively your own ranking with Google and the email address or website you are using as your link source.

It is much better to leave a relevant comment which shows a) you read the post and b) know something about the topic.

Try to start a conversation were other readers can jump in and this will not only improve the ranking of the site you are commenting on but your relevant link which can be your G+ profile or another website.

If I go to the trouble of leaving a comment I will always follow this system. That way I get traffic back to my website or G+ profile when people see I have something relevant to say.

Always remember that most work you do online can be tracked and indexed in some way and if you post wishy washy comments that are not helpful then you will get noticed and de-ranked.

Always work on your brand by being professional in everything you do and don't think of this type of work as a waste of time as a lot of decent focused traffic can be gained by using this method properly.