If you leave your estate through your Will, it must be probated and does not avoid probate.
Convenience: If you don't want to handle the everyday administration of your investments, your trustee can handle all the details, including paying your bills, making your investments, filing your tax returns and earning an income on your assets for your support.
Privacy: Unlike Wills, which are made public after death, trusts may remain private and are not a matter of public record. Also real estate can be deeded and transferred with Trust language in the deed itself so the Trust doesn't need to be recorded in the Public Records.
Retain Control: Even if you transfer assets to the trust, you still have control of the funds; you can appoint yourself and/or your spouse to be trustee and manage all your own investments, sales, etc..
However, you can if you desire appoint a successor trustee to manage them for you if you are unable to do so. You may also have the right to revoke or alter the trust at any time.
Avoid Probate: While you are alive, if you transfer your real estate and personal property, bank accounts, stocks and securities into a revocable living trust, you can save on after death probate expenses (which usually cost about 3% of your estate).
While your trust still must pay for your debts and expenses after death, there is little, if any, delay for your heirs/beneficiaries.