As for many chemical processes, temperature needs to be carefully monitored. The Maillard reaction proceeds at a fairly high temperature of 130 ºC/265 ºF. If the meat surface is covered in water, the temperature will stop climbing when it reaches 100 ºC, at which temperature water evaporates and you can't really go any higher than that. This is why when you brown the meat, the surface needs to stay dry so that the heat will exceed 100 ºC. However, if you over heat the meat, at 180 ºC or higher, pyrolysis (a.k.a., burning) kicks in and it will burn the meat instead. I guess the Maillard reaction is one of those high-maintenance reactions that require your undivided attention. Luckily for people like me, who have short attention spans, browning happens fast and it usually takes 2-4min per side of the meat.
Happy browning, my carnivorous friends!