The hierarchy of slides goes something like:

    Relevant images which support the speaker
    Relevant graphs, rendered for projection
    Relevant microcopy which gives context or focus
    Relevant videos which are kept as short as possible
    Bullet slides which double as effective microcopy

    Bullet slides which double as speaker's notes
    Most slides which animate in point-by-point
    Irrelevant or unnecessarily long videos
    Unreadable diagrams
    Unreadable walls of text

The zeroth rule of presentations is don't waste your audience's time.