The path in your tomcat-maven-plugin configuration
<path>/services/userinfo</path>
defines where you are deploying the webapp (the context root). In this case, you are deploying it to
http://localhost:8080/services/userinfo
Check out the webapps directory in your Tomcat installation.
Since you are defining the CXFServlet mapping as /services/*, the CXF service list would show at
http://localhost:8080/services/userinfo/services/
When you re-defined the mapping to /*, it just appeared to work as expected, but that was only because the context root you used and the service listing path you expected were the same.