She lost Control of Epona

Epona had always been a proud, spirited animal. She permitted neither bridle nor saddle, and if she didn't like the person trying to ride her, that person couldn't. Malon had often explained that lesson to others over the years, but she herself had never experienced it.

Until tonight. As she was riding her around the race track, Epona suddenly wanted to leave the ranch, and there was nothing Malon could do to change her mind. Epona broke into a gallop with Malon desperately hanging onto her, and she jumped over the ramparts to Hyrule Field.

"Epona, no!" Malon protested. "Take me back! Take me back!" But Epona ignored her, and continued to run through the night.

At that moment, Malon realized how **** she was. She could throw herself from Epona's back and get little more than a few bruises, but then she'd have to get back home naked through the front gate, which with her luck might even be locked, and it might not be until noon when her father woke up enough to open the gate for her, which would lead to questions that she didn't want to answer.

Of course, the alternative didn't appeal to her either. She could stay on Epona's back, traveling further and further from home until the horse finally decided to listen to her.