A superb covering tackle from Wallaby replacement Ryan Cross saw Habana narrowly fail to ground the ball close to the left-hand corner flag at a point when South Africa trailed by just seven points.
"At the end of the day, we, the Springbok team, pride ourselves on execution on specific things and I wasn't able to execute," said Habana, who left the field with a shoulder injury immediately after the incident.
"For the standards I set myself, I feel I let the team down in that situation and I think I should have maybe finished off better after having played a lot of rugby.
"For the pressure I put on myself to make a difference and make a huge contribution to this team, I let myself personally down and the team down as well.
"You don't get many opportunities on the international circuit to execute . We had a couple of executions tonight which didn't go to plan and that probably cost us the game more than what the Wallabies really beat us."