Can’t be fagged.
“Let’s be clear: Le Coq is not promising gastronomic fireworks. It’s an upmarket Nando’s. I mean that in a good way. It’s dinner out for those who can’t be fagged to cook and can afford this as an alternative. Yes, I know. Remember, this is Islington.” — review of the new restaurant Le Coq in The Guardian, 9 Nov 2014
“If you can’t be fagged to lug it all with you, there is now a company called HQhair.” — Sunday Times, 2002
Here are the Oxford English Dictionary‘s many definitions of fag, the first few of which presumably account for the meaning of fagged above: 1) v.i. grow weary or less eager, flag; 2) v.i. work until one is exhausted; toil, exert oneself; 3) v.t. make thoroughly weary; tire out, exhaust. 4) v.t. in a public school, of a senior boy: use the services of (a junior) for menial tasks 5. v.i. in a public school, of a junior boy: perform menial tasks for a senior. Also, formerly, in cricket: act as a fieldsman to a senior boy (usually followed by out) 6. v.t. naut. unravel the ends of a rope. As a noun, the OED defines it as 1) something that hangs loose, a flap; 2) a last remnant, a fag-end; 3) a leftover strip of land, tufts of last year’s grass not grazed down; 4) a cigarette.
For more on the now obsolete tradition of fags and fagging in British public schools, see this article on Wikipedia.
Can’t be arsed: “Brand, 38, told Paxman, 63, that he had never voted because of ‘absolute indifference and weariness and exhaustion from the lies, treachery and deceit of the political class’. Paxman responded: “If you can’t be arsed to vote, why should we be arsed to listen to your political point of view?”” — reporting on Jeremy Paxman’s interview with Russell Brand, Daily Telegraph, 5 Nov 2014
The Brits’ way of saying “can’t be effing bothered”.