louis has to be the one to write the tell all because i trust him to give it to us straight. if harry wrote it it would be the vaguest thing ever written entirely in acrostic poetry and like, Significant Embroidery and would communicate literally nothing, zayn would interrupt every chapter to be like “and then i smoked weed and had sex with five fans at once”, liam’s would be a) ghostwritten and b) written way too diplomatically and he would only mention bad things if they could be respun as funny anecdotes. and nialls would be the same as liam’s except with even less information