If we are looking at this from the perspective of Louis XIV himself, his greatest success was his ability to keep France stable, with himself firmly in control, for his long reign. He (with the help of Colbert) was able to enact policies that made France economically powerful and allowed him to build the sort of court facilities at Versailles that made him the envy of other monarchs and emphasized his power.
The major failure of his reign was that he overreached, particularly in foreign affairs. Louis fought too many expensive wars that did not really help France. By doing so, he ended up impoverishing the country to the point where he died ruing how badly he had overspent on his wars.
The early part of Louis' personal reign (after the death of Mazarin in 1661) was marked by several controversial changes to the government and council.
The period was highly successful in terms of both internal and foreign affairs. Within France judicial structure was reformed (however several contradictory and confusing laws were un-modified) and urban law was improved. Further afield, commerce, industry and colonies were tightly controlled and protected.
Louis was also successful in war. Throughout his reign he had fought wars with most European countries. During the 'War of Devolution' Louis was able to gain valuable towns in Flanders, while the 'Peace of Nijmegen' gained further territory in Flanders. However, wars in the final decades of Louis' reign weakened France and its resources.
Louis' love of the arts also provided the opportunity for France's classical age. Artists, literary greats and sculptors were all supported (or sponsored) by the monarchy. The Louvre and Versailles epitomise of this obsession.
The greatest success of King Louis XIV of France was to make France a great power and expand its borders. His achievement also included the Court at Versailles that became the power center of Europe. His long reign also ensured stability in France, even if the government was in the form of an absolute monarchy. He also controlled the church and did not allow it to overrule him. He made himself the supreme ruler and made France a center of art and culture.
His biggest failure was bankrupting the French treasury. The court at Versailles and the expensive wars meant that French coffers were empty and could not sustain the King's wars. The Spanish Succession (1701-1714) ruined the treasury completely and the king could not raise enough tax money to continue his efforts.