I agree with Nimitz's perspective pertinent to "good in-site indexing (ie well structured navigation)" I tend to be a self learner and encounter much frustration in on-line manuals lacking a good site indexing. A search is usually ineffective as it depends on knowing key words being used pertinent to a problem or solution being looked for.
For example I recently in the past week just down loaded Abantecart v1.2 (currently using a different shopping cart) and run into frustration trying to learn how to configure and manage the cart by jumping to Wikipedia, this forum, and available install and user manual. It's also initially a bit confusing that useful extension that are desirable are browsed for in the extension store and no clear advice is disclosed if it integrates to work properly with the most current version.
For the most part I'm discovering Abantecart is robust and allows one-way-or-another easy configuration changes but some are bit more difficult with little if any clues provided. I also like the extension capabilities or rather he ability to easily customize that extensions provide.
For example, eventually I would like to remove the donate button that currently resides besides the "Powered By AbanteCart" text in the footer. The reason being the donate button on the fielded shopping cart I feel will confuse customers as to why and to who they are being asked to donate money. I was actually browsing the forums looking for a solution clue to do something else when I stumbled onto
http://forum.abantecart.com/index.php/topic,2677.0.html .
Two adequate solutions were provided to remove the "Powered By AbanteCart" text. I certainly went to the file in HTML mode and looked at the code and even so in the new version it is on a different line and I will need to study the code a bit more to find the donate button code and either delete it or turn it off.
This points out another confusion factor of having a new version fielded while legacy versions are fielded that have significant code differences. It mat be wise to have separate legacy version documentation and current version when the newest current version has significant code changes.
Overall Abantecart is growing in favor with me, it's just taking a bit more time and effort than I anticipated to get cart in use on my wife's (The Gift Basket Lady) website.
I just Google searched "wordPess" and the what improvement gain it is expected to provide Abantecart end-users appears unclear to me. WordPress appears just to be another type of web content management system where the usefulness is determined by the quality of the content created that appears to be blog and discussion forum oriented rather than in itself being the manual.
I forgot to mention I searched YouTube and found how to configure Abantecart help videos. How to video are great, but here again the usefulness of such videos is keeping them current. The effort in managing video availability with current and correct information is not resolved by wordpress as it requires human interface more so than the "specific" platform making the videos findable and available.
Although digital and word processing technology makes paper somewhat obsolete a technical or user manual still needs to be structured with chapter content list (sections) and important word/key word/critical information word indexed. In this regard Technical writing is performed by a technical writer and perhaps seeking out a technical writer may be more useful than playing musical forum, blog template switching as switching online format presentation still needs the effective technical manual and user manual to employ on the web for others to use.