One basic and very obvious reason to keep your place secure is the residential lease agreement. Most rental agreements require maintaining and returning the apartment in the same condition as rented on the first date of the lease. Some include extra insurance fees. Others ask for strict adherence to the rules of the overall security system for apartment renters for the whole building or set damage compensation fees for lease security violations. Just because you don't own the apartment doesn't mean that you won't be held responsible for thefts, burglaries or robberies when something happens.
Having more people around in a building is not a guarantee for a peace of mind in your own apartment. Disabling the general access control security system for the apartments can create an abundance of opportunities for thieves; it's like having a dozen of separate mini houses with no security at all. Criminals often rely on renters' negligence and lack of interest in security when there are more people around or when the building has a security guard. Apartments are more vulnerable via open windows, simple lock-and-key options and the fact that most renters believe that someone else will notice the crime. Owning a peephole and changing the door locks won't prevent home invasion in a busy building. This is why you should consider installing an apartment security system that works for your needs and keeps your home safe, especially when there are so many different and scalable alternatives.