Targeted traffic is always the best in terms of proper audience, return visitors, sales, partnerships, etc., etc.

Is there a time when any and all traffic is good? In other words, does "non-targeted" traffic add any good to the traffic flow to a site? Does it add to the site because hits are increased?

And what is the bad of "non-targeted" traffic? Consumed bandwidth? etc.?

Dave

I think you've mentioned all the good points of non-targetted traffic... now for the bad...

Waste of resources. Not only does it waste your money, but can put an unnecessary strain on your server and so can cause problems with delivery to the targetted traffic that brings more income.

The Undesirables. Be careful of accepting traffic off any old site, particularly if you want to rank well in a theme engine... I'm sure you wouldn't want your non adult site being "related" to an adult site purely because one or more link to your site and Google has picked up on this.

Confusion. Targetted traffic will know more about the topic so are less likely to ask silly or annoying questions... somebody clicking on a link to make money from the internet and landing at your webmaster resources site for example may need to have the connection explained to them... confusion is not really good for conversions.

Spam. Then there are people who'll visit your site purely with the intention of trying to sell you something (or to pull your email address from the site)... while some may have genuine and relevant offers, most will not...

HTH