It happens before anyone is expecting anything good, so it’s free from the poison of self-consciousness. As a recording engineer, I always record the first take, no matter what it is, a singer in a rock band, or a voice over for a commercial. If the casting and talent are good and the script is well written, you will always get something great in the first few takes. The more takes you record, for whatever reason, similar to saying a word over and over, the performance loses its meaning and believability. It may be technically better in some way, but the human connection diminishes.