Given that winning a championship is considered as the highlight of your career, losing it on purpose is something that (in terms of storyline) that anyone would want to avoid. It must then take someone pretty noble to become a champion and then be selfless enough to give it up voluntarily. Or a McMahon, if history is anything to go by. Both Vince & Shane McMahon have given up a championship in the past. Shane let go of the European Championship in 1999 because he wanted to remain an undefeated champion. He later awarded it to Mideon because he found it in his bag. Vince won the WWE Championship from Triple H, only to voluntarily give up the championship, rendering it vacant. From any standpoint, voluntarily losing a title doesn't really make any sense. Why bother going to the effort of winning a title if the intention was to give it away again? It makes the title seem less important, and whoever gave it up seem either stupid, crazy or both. Luckily examples of champions simply giving up their title are few and far between.