Why are many of my short story selection unfinished?

 A lack of interest 

The short answer to my question is a lack of interest from readers. What is the point of writing a story if nobody will read it?

Underpinning the short answer are several factors.

Some of the stories I lost track of where the plot was going.

Some stories grew too large for the blog, and with no possible publisher being interested, there was little point in progressing with a project which could have lasted months.

A few of the stories I lost interest in writing, they were the exceptions.