In my opinion, Common Lisp is not a hard programming language to learn, especially comparing it to such a language as C++. What is hard is getting the proper environment at the beginning. Here a potential newbie typically has the two general recommendations from the community.

The first one is to use Emacs+SLIME+SBCL (or Clozure CL, …). I should say that this is what I, and most of the other Common Lisp programmers, use most of the time and for a reason: it is an incredibly powerful development environment, probably the best one among environments for the dynamic programming languages. On the other hand, it might be difficult to set up and Emacs might seem weird for a beginner. It takes some time to tame it. In fact, to manually configure Emacs as a Common Lisp development environment one should be familiar with another Lisp (Emacs Lisp).

To overcome this issues a newbie must not lose the spark of interest from the very beginning. For someone, this experience might be overwhelmingly frustrating. It should be noted that such a user might be potentially a good programmer, but he or she just happens to have a somewhat different background. The fact that there are some projects which bundle Emacs preconfigured as a development environment for Common Lisp lowers the entry bar somewhat, but it is not always enough.

The second option is to use a freely available, proprietary, limited version of a commercial Common Lisp programming environment, be it Allegro or LispWorks. Despite the limitations, this option is viable for a beginner who wants to try some Common Lisp if he or she does not mind the limitations. There is always an option to move to another development environment after the initial learning phase.

From analysing the options above it becomes clear that there is a niche for an easy to install, open source Common Lisp implementation which provides a familiar environment for the most commonly used operating systems - Windows. The fact that Corman Lisp is one of the few implementations which have its own integrated development environment makes it a good candidate to fill the niche. Lowering the bar of entry is important, as it might help to attract more users to the Common Lisp. In my opinion, it is something which it desperately needs.

I should say that lowering the entry bar for a beginner is one of my main motivations behind contributing to the project.