I've tried to hire in the Philippines for 24/7 operations and have had a hard time... there just doesn't seem to be a big community, or as the article says, everyone leaves.
If you need someone in that part of the world, it seems like you're best off going to Singapore. Better English, more educated, more business friendly...the list goes on and on. The good Filipinos will have gone there, as you said.
I think it also depends on the type of operations you're looking to hire. I've found that people with stronger skill sets (for example, engineers), are very difficult to hire for swing or overnight shifts, even if salaries are double or triple the daytime shift.
(I run 24/7 operations in Vietnam, I'd love to talk shop.)
There's a lot of factors why people leave but the top two reasons are salary and management.
LobangClub from Singapore has relocated to the Philippines. When I asked them why, it's because they're convinced they could hire Python talent cheaper than if they did it in their own country.
That is not the only reason. There is also the issue of quantity. 1% of Singapore is very very different from 1% of the Philippines.
Turnover is a big challenge. Pinoys aren't always motivated purely by cash. I lived there from 2008-2010 and filipinos are very receptive and intelligent people.