If all goes well, the LED will light up for a few seconds, before fading away.
When the capacitor is charging, the LED is ON.
When the capacitor is close to fully charged, the LED is slowly fading away.
When the capacitor is completely charged, the LED is OFF.
The behaviour of the LED tells us something important about the capacitor. It tells us that the charging rate of the capacitor is not always the same (constant). In fact, the charging rate of the capacitor decreases as the capacitor gets closer to fully charged.