share buy back of SIA

$SIA (C6L.SG)$ I am not an expert in stock trading but having said that if a company like SIA is willing to buy back their shares means that the share price of its company has come to an under value and the directors or bosses of the company felt it's worth buying hence is a positive signs that they have confidence in their company. at least SIA starts buying back immediately after they declare not like some company took months for buyback.