When choosing keywords, some numbers matter more than others. Search volume shows how many people look for a keyword each month, while keyword difficulty shows how hard it may be to rank. Another important factor is search intent, which means the reason behind the search. For affiliate sites, buying intent is very important because it leads to sales. Cost per click can also give a clue, since higher values often mean people are ready to spend money. It is better to look at all these together instead of just one. Which metric seems most useful when picking topics?