The amount of insurance coverage that a person should get depends on multiple factors:

Number of people dependent on you

The more dependents you have, the higher the life insurance pay-out will have to be, to take care of them after you're gone.

Your current & future lifestyle expenses
For the loved ones you leave behind after your demise, you must calculate your expenses and get a life insurance policy with a matching pay-out. This is because, more often than not one tends to forget to bear lifestlye in mind when deciding the insurance coverage.

Your debts
Not only do you leave your house, car and business to your dependants post your death, you may also be leaving them your debt through unpaid house and car loans. Arrange to clear off your debts, or to have an insurance pay-out large enough to clear it for you.

Your investments /savings
If you are confident of having ample savings and investments to help carry your dependents through their lives without you to provide for them, then choose a policy with a lower pay-out and consequently lower premiums. If not, do the opposite.

Given the aforementioned factors, experts advise individuals to multiply their current annual income by 10 in order to determine a rough insurance coverage amount.