Why do some of the recommendations not appear in the Recommendations report?

Note from BRE:

"The recommendations in the Recommendations Report are grouped into the following sub-sections: short payback (up to 15 recommendations), medium payback (up to 10 recommendations), long payback (up to 5 recommendations), and other recommendations created by the energy assessor."

So if for example more than 15 recommendations have short pay back some will not be included.