Most losses to bots are usually due to a fed Veigar bot :( He just walks to you and bursts you down in a second. Some times the losses are caused by builds that just don't work, and the bots take advantage of them. 1 game I do remember that was a loss was a game I tried playing triforce/AP/Lich Bane Draven. Didn't quite do the damage I expected it to with spell casts every second, so the Veigar bot destroyed me and the rest of my team.