I let Jacob get too close.
Miranda could have taken the easy route and typed this up on the touch-screen computer. But this list was different from the others. It wasn't a report, or a dossier, or a conclusive document. This list was something she had to feel with her own hand and see with solid texture, not the holographic screen of the computers.
I let you get too close to Oriana.
She made a great effort to keep this habit of hers secret. Despite wanting more than anything for people to believe she was perfectly human just like them, she couldn't afford that with the mission at hand. They had to believe she was the dynastic ambitious Cerberus leader they were promised. So she kept this minuscule thing with her at all times, well aware of how pitiful it was. Her father would likely never read this. Nobody would.
But she knew her mistakes existed, and that was all that mattered.