When they do that it sets a chain of events in motion which may or may not have a good outcome. If it is immediate and aggressive, the police have few options. If it is not immediate and the police can get negotiations started, it may have a better outcome.
The story gives little to go on as is typically of our modern sensationalist press.
I don't know if you've noticed, but more and more cops are declaring anything that frightens them an "immediate" threat and simply blowing people away.
Police "negotiations" are SO 20th century. Try to keep up.