I disagree with the statement above. Primarily, the main purpose of the Great Panathenaia was to in the same as in the Lesser Panathenaia. The Lesser Panathenaia sought to honour the deity Athena by the means of a procession which started at the Diplyon Gate and headed through the city to the Acropolis. To honour Athena, the Athenians sacrificed many cows and sheep. The peplos was made by the women of Athens Polias in her temple. The Lesser Panathenaia also had many sporting events like traditional dancing, boat racing and a torch lit race, etc.
The Lesser Panathenaia was a local event, in which only Athenians could take part, so they could not have been possibly be showing off their greatness. Later in 566 BCE, the Athenian tyrant Pisistratos expanded the Lesser Panathenaia into the Great Panathenaia, which was modelled on the Olympic and Pythian Games. The new sporting events introduced from the Olympic Games included running, equestrian events such as chariot racing and the pentathlon.
The musical events included rhapsodes (reciters of poetry) retelling passages from Homer’s Odyssey and Iliad.
There were also competitions for who could best play and accompany the lyre and aulos. As a result of these new events being introduced, new introduced and spectators began to come from all over the Greek world. Some also argue that in the Great Panathenaia, a very large peplos (robe) was made foe Athena Parthenos. The aim was the same, however if an additional peplos was made for Athena Parthenos in the Great Panathenaia, then in that year the Athenians had expanded their festival to honour both Athena Polias and Athena Parthenos.
Athenians themselves were not trying to show off their greatness, instead the effects of the expansion of the festival made it seem that way. The introduction of new events, attracted more participants and spectators, who saw the wealth of the Athens, which by reflected in the new grand festival. They also saw the great architecture of Athens, and in particular by looking at the new temples which were recently built in the 5th century BCE, such as Parthenon on the Acropolis.
The prizes of the events also increased Athenian prestige, such as amphorae of olive oil. They gave olive oil because Athena’s present to Athens was an olive tree and by giving the victors olive oil, they kept the tradition. However, as a result, it showed their wealth in oil, so that60 amphorae of oil could be given to a winner of chariot racing and one amphora contained 40L of oil. The amphorae of oil also contained paintings of the sporting events on one side and a picture of Athena Polias on the other side.
This indirectly showed of the skills of Athens in arts, painting and pottery. The prizes of the musical events involved olive crowns in gold and shoed Athens’ wealth. The fact they also gave prizes to the second place winners also showed their wealth. Taken together, the expanded games and expensive prizes given to both first and second place contestants served to showed the greatness of Athens, and increase its prestige. However, welcome to the Athenians, the primarily purpose to honour the city’s goddess was served.