If - before you fly - you have doubts about your mission/location, etc. - DO NOT FLY
I smiled when I read this one, it's a very good suggestion.
Many times during the first year flying my P3P, I remember planning flights using Google 3D maps, looking for interesting POIs and dramatic shots to capture in locations safe and legal. Then, when I show up and assess the area in person, I don't fly for various reasons. It could be wind, too many people, water, too many high wires, or just a bad feeling in general. Most the time I have gone back and flown the exact areas successfully (better weather, less people, etc) but my feeling of confidence was better than the first visit. If it doesn't feel right, I don't fly. I'll wait for better conditions on another day.
That said, now 3yrs later, I will rarely find a place I'm uncomfortable flying if the area is legal and safe, unless the wind is howling. Today I actually seek out more risky flights to capture interesting shots. When I say more risk, I mean if the craft goes down for any reason, the craft is gone forever, such as over water, or in unreachable rugged terrain, etc. Although I use a tracker, many places I fly, a tracker is not going to help retrieve the craft, even though I know where it is.
I don't fly high risk missions when it comes to putting people or property at risk, because drones can fail occasionally. I've been selling embedded industrial computer solutions for 20+yrs. One thing I know is electronics can fail, and these craft are very sophisticated, technology-wise. I always try to fly a path to minimize risk to others, in case the drone fails to fly as expected some day.
If I lose a craft, I'm OK with it. My newest craft,
P4P, has provided me with way more than $1500 of fun and income, so I'm OK with it, other than my emotional attachment to craft firmware 1.3.509, which is awesome, supporting freedoms that newer firmware cannot.