The paranoid techno thriller “Person of Interest,” which ended its third season on Tuesday night on CBS, is subject to all the conventional wisdom about why broadcast drama is inherently inferior to cable. It presumably faces network censors and meddling executives; it passed through the homogenizing pilot process; it’s produced by committee over a long schedule (with 13 writers credited for this season’s 23 episodes).

Yet somehow it manages to be infectiously enjoyable, an attribute that is grievously undervalued — and in short supply — during our so-called golden age of TV. What’s so great about short seasons tightly controlled by visionary creators if the results are leaden pretension (“True Detective”), ingrown melancholia (“Mad Men”), arch preciosity (“House of Cards”) or narrative stasis (“Game of Thrones”)? Just to take a guess at this year’s Emmy field for best drama.

“Person of Interest” is nowhere near perfect. The dialogue is rarely more than serviceable. The action and gunplay are often pedestrian. Over the course of a season, it will have its share of inferior, wrongheaded episodes; this time they were concentrated around the midseason death of Detective Carter, played by Taraji P. Henson.

But along with a handful of other shows — “Grimm” on NBC, “The Good Wife” and “Elementary” on CBS, to a lesser extent “Nashville” on ABC — it makes an argument for the continued resilience of the broadcast model, with all its imperfections. These shows are not just lighter and brighter but also better acted and more narratively engaging than a great majority of cable dramas. They demonstrate that with good judgment and, crucially, flexibility, a long-season, assembly-line series can be more than the sum of its parts.