Three sisters who suffered devastating injuries in a hammer attack by a thief are suing the owners of the London hotel where it happened.
Ohoud, Khaloud and Fatima Al-Najar were staying in adjoining rooms at the Cumberland Hotel in Marble Arch when Philip Spence hit them with a hammer.
Spence was able to enter their seventh floor room, which was open, after he walked in off the street in April 2014.
He was convicted of three counts of attempted murder a year later.
The "hotel creeper" was initially ordered to serve life with a minimum of 18 years, but this was increased to 27 on appeal.
At the start of a case at the High Court, lawyers described the injuries to the women, who were from Abu Dhabi in the UAE.
Ohoud was left with five per cent brain capacity and will require care for the rest of her life; Khaloud has had 20 operations to rebuild her head and face; and Fatima cannot taste or smell and has problems with her memory.
The family's barrister, Susan Rodway, said Spence - who had a history of sneaking into hotel rooms to steal - had "great knowledge and familiarity" of the Cumberland Hotel.
She said he told his criminal trial he was a "regular intruder" at the hotel and had even been able to "sleep in maids' cupboards".
She added security "failures" led Spence to directly "target the hotel", where he knew he could make "an easy buck from the rich pickings there".
The court heard it was "well-known" to the hotel that it was "common for Middle Eastern guests to leave doors on the latch" to enable family members to go between rooms.
The hotel's owners deny liability, arguing that by leaving their door open the women "voluntarily assumed the obvious risk of allowing anyone to enter the room while they were asleep inside".
Neil Block QC, for the hotel, said in a written submission: "Each guest room was fitted with a heavy duty fire door with efficient self-closers and automatic locks, deadlocks, security chains and spy-glasses. The rooms were designed so that guests could not leave them open accidentally."
He said that after the incident "police subsequently tested a closed bedroom door and found it impossible to gain access with a hammer similar to that used by Mr Spence".
Ms Rodway said the hotel's CCTV system was "purely reactive" and that "it was clearly only there to enable review should an incident occur, but not to enable any anticipation or prevention of an incident".
But Mr Block said the fact that "there was no system for live monitoring" of all 130 CCTV cameras at the hotel "was, and indeed remains, the norm for similar hotels".
He concluded: "But for the deliberate interference with the door's locking mechanism, the attack would not have occurred."
The case is expected to last for two weeks.