A mote must grow as well as glow. Each stage has a limit on how bright it can burn, so filling the bar early just means waiting for the next form to raise the roof. Only an adult can reach 100 and go home.
The six shapes a mote can end as, each burning at 100. Adult auras take the colour of the spirit that shaped them — which is how you can name a mote's kind across a dark clearing.
The same sylvet at five radiance levels. Note what does not change: neglect takes the light away, never the creature. A dark sylvet is still a sylvet.