These sorts of questions should concern you, because they can help you develop a site which is specifically addresses the needs of the people who use your website.
Philip Greenspun (author of Database Backed Websites, (available online at http://photo.net/wtr/thebook/) offers a number of free services for web publishers which help address some of these issues.)
Clickthrough.net (http://www.clickthrough.net/click/) gives webmasters the ability to count the number of times certain files or web addresses are visited from within their pages. Specific information about certain files may also be obtained.
The ability to see what files or sites are being looked at can give webmasters a much better idea of what sorts of things the users of the site actually wants, and also gives some idea of the usefulness of linking to other websites.
LUSENET allows users to make comments about a site, or to post questions and answers. This service can be freely available to all users of your site, or it can be password protected. JCSAV has a Q&A forum using this service. Users can post questions and other users can answer them, all without having to email the JCSAV webmaster at all. The questions and answers are created as a dynamic web page every time someone looks at the page, with the information coming directly from a database.
These services are database-backed, which is why they are freely available. Philip Greenspun doesnt need to do anything to set up extra files for webmasters - the system essentially runs and maintains itself. Visit Philip Greenspuns website (http://www.greenspun.com) for specific step-by-step information about implementing some of these ideas. Philip Greenspun thinks that these services are now out of date - he calls them "legacy" Services - and recommends that people with access to a server consider using OpenACS (Open Architecture Community System) instead. This is an advanced toolkit for building scalable, community-oriented web applications, available at http://www.openacs.org.
Another helpful service which is freely available is to add a counter to your page/s. Fast Counter (http://www.fastcounter.com/index.html ) offers a service which takes 5 minutes to set up and add to your page. Fast Counter even gives you the HTML code which needs to be added to your site. Weekly statistics can then be generated, showing how frequently your site is visited. Counters don't need to be visible to the public. JCSAV's counter is reduced to a 1 pixel by 1 pixel dot. It still functions as a counter though.
The counter is not so important if you administer your own web server. Web statistics packages are available which can sift through the access logs and give you information about where the users came from, how long they spent in your site and which pages they visited. This will not tell you where they went when they left though. For this you need something like the service offered by clickthrough.net.
With a little planning and work on your site some useful information can be automatically generated for you. This can in turn help you make decisions about the future direction of your website, and help make the site much more useful.
A free, automated site inspection is available at http://www.siteinspector.com. This gives a general idea of how your site is performing, and makes suggestions for improving it. There are many other sites which offer similar services, this is just one that I have used in the past.
Validators such as the W3C HTML Validation Service at http://validator.w3.org and their Cascading Style Sheets Validation Service at http://jigsaw.w3.org/css-validator/ will help ensure that the pages you create have been made using correct coding techniques, and comply with accessibility requirements. Many tools are now available help you comply with Web Accessibility Guidelines. The best list of the tools is available at http://www.w3.org/WAI/ER/existingtools.html.
W3C's Link Checker, at http://validator.w3.org/checklink
will also help determine if links to pages within your site, and links to external
sites are still working. Of course, the content isn't checked, just that the
URL still exists.