Since production is setup with very high security passwords get locked easily. In a big team of developers someone might enter the old password several times and lock a username which everyone shares. After which it becomes a problem setting a new password as all the old ones cannot be reused. To fix this problem set the following profile option value to NULL.
I also like to keep a session alive for several hours on a non production instance as I keep getting in and out of the instance. Hence I change the following profile option to 300 for 300 minutes, i.e. 5 hours.