When you put things like life insurance policies, IRA accounts, annuities and 401(k) accounts in place, you are asked if you would like to name a beneficiary. You can also put a beneficiary in place for things like checking or savings accounts, brokerage accounts or CD accounts.
When a beneficiary designation is put in place, then the beneficiary receives the asset at your death directly and that asset never makes it to your will for distribution. Therefore, the provisions and wishes in your will have no impact on the particular assets with beneficiary designations.
However, if the person you named as your beneficiary passes away before you do, or if somehow your beneficiary designation never gets recorded appropriately in the records accompanying your asset, or if you forget to name a beneficiary for the asset; then the beneficiary becomes your estate and the provisions and wishes in your will are going to control the distribution of those assets.
If the beneficiary who you thought was going to get the specific asset and the beneficiary under your will are the same person, the process of getting the asset to the beneficiary may now be a bit more complex (because now probate may be involved) but the result is going to be the same. But, if the beneficiary for the specific asset and the beneficiary under the will are not the same person, then the person who you thought was the beneficiary for the specific asset will receive nothing and the beneficiary under the will is going to receive the asset.
So what is the moral of the story – check your beneficiary designations. Every year, request in writing, an acknowledgment from the company in charge of the paperwork for your asset a confirmation of who they have listed as the beneficiary for that asset. Compare their records with your wishes and make any necessary changes before it becomes too late.