When the SEC asked to put those signs in the roundabouts the traffic safety office said no. You can't put something distracting with such small text somewhere that demands your full attention to the land cruiser on your right which is about to turn left across all three lanes. (some paraphrasing here)

But they "went through another door" and now the signs are everywhere. I hope they got some funding from the panelbeaters association or Toyota Genuine Parts.