When you buy a game at a toy store, it usually comes with an instruction manual. The manual defines the rules of the game, the number of players, the final objective, and so on.
The same is true in Judaism. There is an instruction manual on how to practice it, which is the Shulchan Aruch—the Jewish legal code. This code is based on the Talmud and its commentators throughout the different eras and regions where the Jewish people lived.
One of the rules that appears in the Talmud in different contexts and has its expression in halakha—Jewish law—is ma'alim ba'kodesh—we rise in holiness (lit.). The idea behind this rule is that, given a certain level, when there is an advancement in space or time (whether caused by oneself or not), the person cannot remain stagnant at the level they were at (or descend in level, God forbid), but must advance.
Hanukkah provides a clear example of this principle. There is a discussion in the Talmud regarding how the Hanukkah candles should be lit: Beit Shammai states that eight candles should be lit on the first night, seven on the second, and so on. Beit Hillel states that one candle should be lit on the first night, two on the second, and so on. Why? Because one should strive for holiness (Beit Shammai's reasoning is that just as the sacrifices during Sukkot decrease as the festival progresses, the number of Hanukkah candles should decrease as the festival progresses). The law is like Beit Hillel's, because one should strive for holiness.
What do we take away from this? Beyond the general idea of personal elevation and constant advancement and development in intellectual and emotional terms, there is something else we must consider.
On the first night of Hanukkah, we light one candle. By doing this, our observance is complete. On the second night, however, if we were to light only one candle, our observance (of the mitzvah of lighting candles on Hanukkah) would be incomplete. One candle is missing. This teaches us that the spiritual work and the levels we reached yesterday, even if yesterday represented our maximum effort and personal development, are invalid and insufficient for today. We are expected to grow to the fullest extent of our potential each day—not to the maximum reached the previous day, but to the maximum expected and achievable on this particular new day (which, obviously, is higher than yesterday's). And so on, every day.
This is one of the teachings of the Hanukkah festival that we should carry with us everywhere: maalim baKodesh - always rise up and give your maximum potential in the service of God.
In conclusion, to dispel any possible doubt: it is said of Reb Zusia of Annipoli that he used to say, "When I go to heaven, they won't ask me why I wasn't like Jacob, why I wasn't like Moses, they'll ask me why I wasn't like Zusia"... the most that is expected of each person is what each person can give of themselves, not what their neighbor can give... no more, no less...
Chag Sameaj, a very happy Hanukkah.