It's my favorite platformer series from Nintendo, while it's not challenging in the slightest (at least in the main campaigns) it's really fun, with awesome music and good graphics, no matter which system Kirby is on. Not to mention, many Kirby games are packed with different modes and mini-games, which are really enjoyable, which is another plus in my book.
and forgot to mention but everyone in these games are so ADORABLE (besides final bosses)