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Why can vessel members transport water faster than tracheids?

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Vessel members are more efficient at transporting water than tracheids primarily due to the presence of perforations in their end walls.12

While water moving between tracheids must pass through a pit membrane—a modified primary cell wall that restricts flow—vessel members have areas where both primary and secondary cell walls are absent. These perforations allow water to flow relatively unimpeded from one vessel member to the next.1

Additionally, as vessel members evolved, they became shorter and wider, which further facilitates the rapid movement of water through the xylem. While this specialized structure allows angiosperms to occupy a wider range of habitats, it also makes the system more susceptible to disruptions, such as air bubbles, compared to the more primitive, restrictive tracheid system.21