Despite being the best, or at least the best-reviewed, new show of the season, “Nashville” (9 p.m., ABC) has seen its ratings steadily decline since midseason. Nothing kills a soapy melodrama like asking viewers to return in three weeks to see what happens next, followed by another two-week hiatus.

In tonight’s repeat, spoiled country pop star Juliette (Hayden Panettiere) is convinced that her virgin quarterback boyfriend’s Christian family has warm feelings for her. (Spoiler alert: They don’t.) And we’ve known that since before Christmas!

Repeats have always been part of the TV season, but they are disruptive to a good show trying to establish itself. And they can be particularly jarring now that an increasing number of viewers — most notably younger ones — opt to consume TV in unconventional ways. Netflix has started releasing original dramas (“House of Cards” and “Hemlock Grove”) a season at a time. Fans of those shows don’t have to wait a month between new episodes. Like staying up all night to finish a good novel, they can devour an entire season’s story arc in a single weekend if they so choose.

Of course, viewers can catch up on “Nashville” on a service like Hulu Plus. But they still have to wait until an original episode is broadcast to stream it there. Some may wait until the whole season is over to stream it in its entirety. But if not enough viewers watch it on good old-fashioned ad-supported TV, ABC may just go ahead and cancel “Nashville.”

That, in a nutshell, is the paradox of contemporary television. Technology brings us new ways to consume entertainment. But no one has yet invented the free lunch.

Tonight’s other highlights:

• Finalists compete on “American Idol” (7 p.m., Fox).

• Deadshot returns on “Arrow” (7 p.m., CW).

• Murder on sorority row on “Law & Order: Special Victims Unit” (8 p.m., NBC).

• On two episodes of “Modern Family” (ABC): a scary prognosis (8:30 p.m.), a college reunion (8 p.m.).

• A unique ecosystem emerges on “Australia’s First 4 Billion Years” on “NOVA” 8 p.m.).

• Signs of a meteor strike on “CSI” (9 p.m., CBS).

• Dawson taps an unexpected resource on “Chicago Fire” (9 p.m., NBC).

• An opportunity seems too attractive on “The Americans” (9 p.m., FX).