In general, a British combatant who died in the First World War is commemorated in at least two ways.
Firstly, he either has an identified grave or else is named on one of the memorials to the missing.
Secondly, he is very likely to be named on the war memorial of the place where he lived. Not every single place erected a war memorial, and the collection of name data was not always rigorous. Nevertheless, the great majority of the dead are recorded on a local memorial.
Over and above this, a man may be named on any number of other memorials - erected, for example, by his school or his church or (if he was not a regular soldier or sailor) his employer.
Finally, in a very few cases, there may be an individual memorial.
Denis O'Brien is named on the Chatham memorial to those sailors who have no grave.
He is named on the Cenotaph by the Guildhall Square which lists all the dead of the city of Portsmouth in the First World War. Though he was based at Chatham, Portsmouth was the home of his family.
He is also named on the plaque by the memorial stained-glass window in the church of Corpus Christi, Portsmouth. That was the church he attended when home on leave.
Very few of those who died at Coronel have an individual memorial. But Admiral Cradock has.