In my mind it really depends on your goals.
If you're working with a funnel or sales pipeline to try to sell your product or services, a sequence can be a great way to drip evergreen content and messages out to those folks over time with the goal of making the sale.
If your list is for timely updates (news, special offers, commentary on current events), then a weekly email is a tried and true way to handle that, but the nature of the content means that it has to be timely and thus won't be relevant if you were to put it into a sequence that folks started getting weeks or months down the road...