The General Medical Council sets UK standards for undergraduate medical education. Entry to British medical schools is very competitive. There are more places for medical students now than previously but obviously not all can be admitted to UK medical schools. The numbers have to be matched to the numbers of doctors required, and as joebloggs has pointed out there is a shortage of the training posts needed for full GMC registration, due in part to the number of EU applicants.
The GMC also sets the standards for qualified doctors, and "revalidation" based on regular appraisals is to be introduced across the UK. The idea is to make sure that all doctors reach and maintain the same high level of practise. Unfortunately "rogue doctors" can never be eliminated. The frustration to the GMC and everyone who rightly expects doctors to be safe is that so far they are unable to apply the same rules to EU doctors as they do to international medical graduates (from outside the EU). To my knowledge there is no news on this since I first posted the thread.
As for the quality of filipino doctors, we've had a range of opinions posted here. I suspect, from what you have said, that the Professional Regulations Commission (PRC) does not set the same high standards as our GMC.