I was the skinniest out of all my friends, and even out of most of the people in my school year. I had never thought about starting at a gym until I met a new friend who had been training for roughly 2 years. After going on holiday with this friend (avoiding standing next to him by the pool) I decided I had had enough of being so skinny and wanted to add some muscle to my frame. I joined my friend's gym and immediately fell in love with the discipline required to grow. I have never looked back since starting and don't plan on it.
The reason i love training is because i have a chance to test myself every day, something which i look forward to more than anything else. Knowing that you're working hard and growing is a good feeling, especially when you look back over your progress and notice gains in size and strength; this is even more rewarding for me due to how skinny and weak i was before i started to train.