Why has the release of Sax been pushed back twice?
Are Syco that desperate to get a hit single? If there is enough demand for the song, then the public will go and buy it.
Just like with Ben Haenow, OA/OS just doesn't work for new artists starting out. They need the build up of airplay as the British music buying public tend to buy music that they are familiar with. There's nothing more familiar than 6-8 weeks of built up airplay.
Second Hand Heart isn't that bad to be honest, and had Syco just put the song up for pre-order and sent the music video to all the music channels, people would've heard the song enough times to decide if they liked it or not. Instead, it was just released without anyone actually hearing the song and it enters at #21 making the song look like it's flopped. There are probably 50k people out there who would love Second Hand Heart but have still not heard the song, hence its not selling the way it could be.
At least Sax has a 90 second preview on iTunes. Even Ben's single didn't have a preview until it got released.