There are several reasons why most steak knives are serrated. Below are some of these reasons:
Blades that are serrated have edges that are less exposed and hollows as compared to the straight knives. It is due to this reason that they are able to make tear cuts through steak and other meats. The teeth-like appearance of the serrated knives, make them suitable for cutting through hard surfaced foods like meats. This is because the teeth are able to catch and rip the meat as the knife passes through.
Steak knives are also serrated to reduce the frequency of sharpening. It is common knowledge that serrated knives do not get blunt as easily as the straight knives. When the straight knives come into contact with ceramic plates, then they become very blunt. In most cases, steak is cut on ceramic plates and you, therefore, will have to sharpen the straight knives every time. This makes serrated knives more convenient because they do not need to be sharpened after every job.
The steak knives are also serrated to prevent edge turning when they come into contact with ceramic plates. Straight knives have to be honed every now and then because they are prone to edge turning. Serrated knives may have the problem, but is only manifests on the tips and not on the valleys. This makes them easier and cheaper to maintain as compared to the straight knives.
With serrated steak knives, you are able to reduce the force you need to slice through the meat. This is due to the laws of physics, that a longer knife has a greater distance and therefore you will need more force. This may be tiring especially since the steak may be a little tough. However, when the knife is serrated, then the force you apply will be greatly reduced. This is because the distance will reduce and the serrations act as hooks.