Many years ago at a BALPA/GATCO Forum discussing airport capacity. An erudite fleet captain with a very respected airline stated that in a capacity strapped situation if there wasn't the occaisional go-around, ATC weren't trying hard enough. I believe he was right. We are all human and will make mistakes. The system in which we work must be robust enough to accommodate these mistakes but should not penalise honest errors. If there are a number of similar errors the system must be changed to eradicate these errors.