It had been different in fifth year, he told himself. That was why he wasn't joining. It was too dangerous now. Now, they risked not expulsion, but their very lives. Maybe the other students were completely prepared to do that. Maybe they were prepared to fight, to the end, no matter the cost. But Terry wasn't. Fifth year, it had been an easy decision. Learn, risk expulsion, and prepare for the coming war— or don't learn, don't risk expulsion, but fall at the first sign of conflict. Easy. Definitely better to risk his wand learning magic that might save his life someday than to not risk his wand, but die because he never learned the spells.
But now it was different. Now, the risk wasn't expulsion. Now the stakes had risen, soared, doubled, tripled, and quadrupled. Now, to be caught could mean death, torture, or imprisonment. Terry knew that. He was sure the others knew that too. Naturally, it didn't seem to really bother most of the Gryffindors. Of course not. They, of course, would do what they thought was right, no matter how suicidal, how dangerous, how hopeless the cause might be. The Hufflepuffs seemed to hesitate a bit longer, but they still didn't hesitate for very long. Too loyal to Harry, he supposed. Even the other Ravenclaws joined pretty quickly, leaving him alone, the only DA member apart from Smith who hadn't joined. And he didn't really count Smith. He was the only one who couldn't pull together enough courage to finish what had been started when they'd signed that paper years ago.
Terry began to despise himself for it. Where was his courage? Had he ever had any? Why was he so cowardly? Why was he watching, in silence, as students were tortured? When he had the power to do something? When he could help?
Terry didn't feel welcome in the common room anymore. He didn't think he was being cast out intentionally—he had chosen not to be involved, and the other students were only respecting his choice. But he avoided Ravenclaw Tower now.
Sometimes he would sit in the library and watch the messages flash across his old coin, which never grew cold anymore, wondering what it would be like to be out there with his old friends, rebelling.
He grew more and more depressed, hating himself for sitting back and doing nothing, for not having the necessary courage to do anything else.
Then one day, as he ate breakfast, he felt the coin grow hot in his pocket. He pulled it out as inconspicuously as he could, and read the message, expecting to see news of another disappearance or murder.
But instead, he saw hope. Hope, which he had thought deserted him completely many months ago.
And the hope finally awoke his long-dormant courage.
So he stood and yelled his hope to the world, no longer silent, no longer a coward. No longer fearing for the consequences.