Stress
There are two kinds of stress when it comes to coding. On the one hand, tech startups often fail. There's often no guarantee from one day to the next that your job will still be in existence in a year, a month, or even a week.
On the other hand, coders are responsible for writing and maintaining critical software. One experienced coder tells this story:
"I worked on the technology behind the blood bank of one of the biggest cities in the world. One day, the system crashed, and it was up to me to get it back up as quickly as possible. My boss called me, frantic. 'Hurry, Krishna!' she shrieked at me over the phone. 'We need blood! Don't you know that people are dying?'"
Now that's stress.