Yes we all make errors but I am trying to figure out the actual points at which this error was not trapped until the technology saved their bacon...
1. Pilot forgets to set flap.
2. Take-off checklist, item missed or incorrect response.
3. Config check prior to rolling, usually at line up.
So three errors trapped by the config warning at thrust lever movement. Draw your own conclusion.
And to an amateur's eye, that looks like a pretty sloppy line-up at the 1st try. My instructor would rip my head off for that. Why throw away 2 a/c lengths of runway before starting your run?
You would need to know the company line-up allowance and policy. If the RTOW was based on say an intersection departure but they used full length then nothing is "thrown away". Not saying that this is what occurred here just explaining that it is often not simply being cavalier with the 3444 metres available to use.