Many years ago, I'd adjusted "newly out-of-the-box" 700 triggers for minimal "competition" engagement, but in the normal "wearing-in" process, they've become too short and refused to cock, but haven't had firing pins drop without touching the trigger. Since that time, many years ago, I've refused to adjust the older 700 trigger design until they've been fired enough to stabilize the mechanism.
Having repaired and "tuned" many types of firearms over the years, I've noticed that many competition shooters and some varmint hunters want triggers as light and as short as physically possible, yet either don't know how or simply fail to maintain them adequately. They use lubricants like WD40 which, in time, congeal in trigger mechanisms, preventing or inhibiting forward trigger movement on cocking. They also fail to protect guns from the elements by not using proper protectants. Yet, they continually use them in terrible weather until they ultimately fail to operate.
For example, people who have driven old, rusty and poorly maintained vehicles for years, should never own a Ferrari or XKE. They simply don't know how to take care of them properly. To some extent, the same goes for finely-tuned guns. Novices also shouldn't be adjusting triggers.
I second the statement by a previous poster about older Winchester 94s being the rifle with the most accidental discharges. I've replaced hammers with broken half-cock notches that caused accidental discharges and have witnessed several hammer thumb-slips that fired the rifles, just after loading. It happens mostly in cold weather when people are wearing gloves or mittens.