One problem faced by companies that fail to invest in security alarm systems is employee theft. This can be a major source of losses.
Often, the best way to secure an establishment is to install different types of security systems so you're not limited to just one layer of protection. For instance, having cameras may help to provide proof that theft was committed but it may not help in preventing the crime in real-time.
In domestic settings, the threat may even be someone you mistakenly trust and let inside your home. Installing house security systems lets you monitor how your loved ones and precious belongings are treated when you're away.