Just ask NBC.
In order to try to garner the highest ratings and maximize ad revenue, NBC is recording, editing and packaging the premier events – Gymnastics, Swimming, Diving etc. – then showing them in prime time as if they're happening live.
Which yields classic moments like this...
Yesterday evening NBC aired a Today show promo for an exclusive interview with "gold medal winning swimmer Missy Franklin" before, if you believe their coverage, her race occured.
You can't have it both ways. Especially in today's world.
With multiple networks all showing live action throughout the day, it would be best broadcast the marquis events in real time (rather than a women's handball game between Korea and the Netherlands), then acknowledge the truth and create the best damn Olympics recap show every evening instead of acting as if the events being shown are somehow going on in the middle of the night in London.
Had they done it, they may not have suffered the embarrassment of the botched promo and hilarious twitter feed #NBCdelayed.