As noted, many people act as their own trustee until their incapacity or death. Others determine that they need financial assistance and management of their assets simply because they are too busy or too inexperienced or simple don=t wish to have the responsibility of day-to-day management of their financial affairs.
Perhaps the most important decision for you to consider is your choice of a trustee to act in your place. As you have read, your trustee will have considerable authority and responsibility, is not under direct court supervision, and will assume that responsibility either during your lifetime (if you so choose), if you become incapacitated, or at your death.

A trustee may be a spouse, adult children, other relatives, family friends, business associates or a professional fiduciary. The professional fiduciary may be a bank or trust company which must be licensed by the State of California. You may also provide for co-trustees. You should discuss your choice with an estate planning lawyer. There a number of issues to consider. For example, will the appointment of one of your adult children cause undue stress in his or her relations with siblings? What conflicts of interest are created if a business associate or partner is named as your trustee? Will the person named as successor trustee have the time, organizational ability, and experience to do the job effectively.