SandLat650 has indentified two common problems for larger UK airports - long waiting time at border control and poor performance from ground handlers with the result in late arrival of baggage. The airport company can't be blamed for these two problem areas provided UK Border Control has enough booths and the ground handler company have a fully functional baggage handling system to work with. SandLat650 also mentioned a third area that may more from airport to airport and also the season, and it's the poor on time performance one can experience at times. These delays tends to increase throughout the day and the last arrivals in the evening are the worst off. Sadly FlightStats has stopped publishing their monthly on time performance reports for airports in January this year. In these last reports UK airports showed a poor performance and could be found mainly in the bottom third. The delays can't solely be blamed on the airports, but also the carriers and ground handlers have to accept their fair share.
Since this was an arrival, it is totally natural that SandLat650 didn't mention two other common areas that create a lot of irritation, and that is long waiting time to check in baggage and ditto queuing to get though security control. The first is not under control of the airport, but the security control is one of the few areas the airport company has full control over. If a security company is hired to perform the security checks, the airport need to assume full responsibility for this service. My home airport is performing below my expectations if it takes more than 10 minutes to get through security. I have still not experienced so many minutes there, but at a few airports in the UK I have spent almost one hour in line to get through security (like on a hot summerday in August last year at MAN's Terminal 3).