This question can be answered by how your property is used. Let's look at a number of different scenarios:-You are the only person with keys
If you are the only one in possession of your keys at all times, then there should be no reason to change the locks other than for a reason to upgrade to a more robust locking system, or if the current locks are becoming troublesome to lock/unlock through wear and tear, and it's better to simply replace than repair.One or more employees have access to a set of keys
If you are practicing due diligence, you are giving your keys to employees under set terms and conditions that preclude them from sharing access to those keys with third parties or making copies of the keys. There's the salient point that you trust them enough to abide by those conditions, but at least they are contractually responsible if they break those conditions. In that situation, there should be no need to change locks regularly. In fact, in doing so, it can instill a sense that you are not a trusting the employees and it can cause ill-feeling.
Obviously, if things start going missing overnight in the office, or you have a reason not to trust these employees, then of course you need to reconsider.
A disgruntled employee who had access to keys has been fired or resigned from your business
In this situation, it's a judgement call. It will depend on the reason for the departure. If they were fired for stealing items, then changing locks should be an obvious, necessary step since they had access to keys.You are leasing the property out to tenants
In this situation, it might be wise to change the locks when tenants move out. While it's a similar situation to giving keys to employees, tenants are a step further away from you, and once they move out, they are not beholden to you any longer. This is a similar situation to the disgruntled employee leaving, but with tenants, it's probably better to have a blanket policy of changing locks. Since changing locks isn't cheap, you might then consider leasing out your property for a minimum of a year or two, rather than short-term leasing. You've just bought the property
If you've just bought the property, then changing locks is probably a good move since you may not know how old these locks are or how many people have had access to the existing keys. Changing locks is one way to guarantee that only you have access to the property. Article kindly provided by greenlocksmith.uk