@breizh Not every character has to be "likable", ya know; in fact, there's times we writers want our audience to absolutely loathe a character, so we engineer every facet of their personality and background to be utterly detestable. Explaining a character's reasoning for doing something can achieve either of these goals, or it can achieve neither, depending on what the author intends. In this case, the intent is clearly to invoke the trope "revenge before reason", where a character is harboring such a lust for vengeance against something that they don't care if the world burns in order for them to achieve it; as the audience, you're not necessarily supposed to
like that character as much as you're supposed to understand them.