Why does Wolf's Rain have four recap episodes in a row?
Episodes 15, 16, 17, and 18 of Wolf's Rain are recapitulations: the story so far, retold in existing footage, four weeks running. No other well-regarded series has a hole in it quite like this, and the cause was not laziness. Bones was a young studio in 2003, fresh off the Cowboy Bebop movie, making one of its first big original productions, and the schedule broke.
The explanation most often given, repeated by Anime News Network's Answerman column and by reviewers ever since, involves the SARS outbreak of 2003: the production suffered unplanned hiatuses as illness disrupted the staff and the studios Bones relied on, and Fuji TV pressed for something, anything, to fill the slot. The honest summary is that the exact weight of each cause is still argued about, but the fact of the crisis is not: the show stopped, and recaps filled the gap.
The consequences ran downstream. With four of its twenty-six television slots spent on recaps, the story could not finish inside the broadcast run, which is why the ending exists as a DVD OVA at all. Critics at the time were blunt about the waste, and the standard advice has not changed in twenty years: watch episodes 1 to 14, skip to 19, and do not buy the recap disc on its own.