Recently, John Chau's martyrdom has made the headlines, both in flattering and unflattering ways. Many people - even Christians - were shocked: partly that he went to a place where the language was less known, and partly because he went to a place that was openly hostile to Christians.
But missionaries go to these places all the time, and are occasionally killed--more often than mainstream news headlines let on. An instance of a martyred missionary is not unusual: nearly every year has at least one published case, and many years have more than one.
Some brief examples:
These cases are just the tip of the iceberg. They are what can easily be found with a few minutes of Google searches. Other agencies have had people martyred, but their names haven't made the headlines, and the agencies in question haven't pushed it into the press. I know several agencies have formal policies about what will happen if a person is kidnapped, or killed, that missionaries have to sign in agreement in advance.
Mission work is not always safe. Jesus didn't promise safety for his followers. The same Lord who offered healing and protection from scorpions and serpents (Luke 10:19) promised "when you are brought before rulers and courts" the Spirit would give us the words to say (Luke 12:11). Jesus said "if they persecuted me, they will persecute you" (John 15:20).
The point isn't for us to be safe. The point is for us to pick up our cross and follow him. "For whoever wishes to save his life will lose it; but whoever loses his life for My sake will find it..." (Matthew 16:25)