[Imladris]

I believe that one of the most important qualities of a character is that the reader be able to relate to him. A good or perfect character can be either excrutiatingly annoying in the hands of an inadept writer or loveable and relatable in the hands of a good one.

Now that I have grown older, I don't look for faults or flaws, I look for how a character acts in certain situations. I look for struggles. Example: Frodo in the Barrow Downs. He could have left. He was tempted to leave. He knew that it would be justified. But did he? No he didn't.

Ender in Ender's Game is, in a sense, perfect (at least I think he was). He's a military genius. But I adored him, and sympathisized with him. It was because along with his perfection, he was also human. He was still a boy placed in adult circumstances.

If a character is perfect, it must not be unrealistically so. He must have struggles. If a character has faults, they must also be realistic. Because if you give a heap of perfections to one or a heap of faults to another, it is still the same coin, only a different side.

And, as Aiwendil said, characters must also be complex.