Coming from a country high in that chart (4th to be exact)... Homicide rates in general are pretty low there regardless of the used method and/or weapon. You couldn't tell when watching the news as it's quite often a big fuss when homicide takes place, but that's because... it happens so little.
Ban on guns is a very important reason. Last shootout we had, was when an idiot just gave a gun license to a person who should never had a gun, and well if you don't uphold a law it always fails... Measures have been taken to never let that happen again. Also that shootout only had 6 kills (don't know if that was including the shooter himself who shot himself afterward), and why? Because nobody tried to play a hero thinking they could take him on, although I am to understand that a few got killed to prevent others from being killed. In stead people hid or ran away and called for qualified people to handle the situation.
There is more than just that though. The Netherlands has apart from a ban on guns, also a system called "TBS". People who commit any sort of crime due to psychiatric reasons, are often forced by the judge to go to a TBS institute for therapy. This is NOT a punishment (mostly they serve that out in jail first), but only therapy to deal with your issues, to prevent you do this again. Point in this is also, when you don't have weapons the temptation to use them also isn't there.. This also plays a role here. When it comes to TBS I can only speak about the Dutch situation, as not all countries have a similar system.
Also no death row. Death row can do more harm than good. People on the run out of fear for an execution literally fear for their lives, and somebody who fears for their life can also become very dangerous. If such a person can freely obtain a gun it's a 1+1 situation.
Although cops carry a gun, weapon stick and some of them tasers, they are instructed to never use those weapons unless there is no other option. Using a gun can cause a suspect to do crazy things, so that's why a cop may only use their weapons as the ultimate last resort.
Now you can never rule out homicide for 100%.. that's an illusion, but the more violence you try to use against it, the more you get back. When you are not connected to criminal networks, you mostly don't have to fear being murdered here.