If the management sees the company grows at 5% and elsewhere...

If the management sees the company grows at 5% and elsewhere capital can grow 8%, then the share buy back is not a sound decision; however if the management sees the company can grow at 10% at current share price and condition then the share buy back is a good decision. It seems the market agrees with the management at the moment. There is no one size fits all as whether share buy back is good or not.