Is this a cautionary tale? If so, black did not secure the group in the lower right. White played the tiger's mouth first preventing black from connecting his group and removing eye potential. Then black played somewhere else allowing white to push, threatening to sever the rest of the group from the corner. Black connected. Then white turned down and killed black.
If this is not a cautionary tale, black played the hane in the lower left. White answered by cutting off the black stone from above. Then black ataried the white stone from below. White defended and black connected. White defended the corner. Black made a one-point jump to the left. The entire white lower side died.
Neither :)
Black was decisive and unyielding, played a small monkey jump from the bottom right in sente, forcing white to attach, and close all the while defending own cutting point, then using that sente to create a second eye in the middle, giving white group some pressure to further enclose the area below, which white does.
Then, sente again, this time by an atari against the bottom left group forcing white to close, and again by slipping a hane below the leftmost white stone.
Then the sente was lost and white did what it could to reduce blacks points.
The end result, if I recall correct, was 21 points for white and 38 for black.