The problem is bealine, LHR isn't much better!!
Terminal One is an absolute disgrace. Anyone arriving into LHR T1. will note the poor decor, (dark green!) lack of air-conditioning in baggage reclaim, the odd lift, escalator being out of order, inbound and outbound passengers 'clashing' along the piers and the horrenduous ques if your a non EC foreign national at immigration. Not a very nice impression to give to foreign nats. visiting Great (!) Britain.
However, its not necessarily BA's fault and I'm no doubt treading over old ground. Big Rod E. has noted that the infra-structure at LHR needs improving but Gatwick on the face of it, seemed like (until the relevations on this thread) a pleasant alternative!