Steven Spielberg’s “The BFG” might have seemed well-positioned to open nicely this holiday weekend. It’s a feel-good, all-ages tale from a popular storyteller that flashes state-of-the-art digital effects. And, well, it’s got Spielberg’s name branded all over it.

But none of those factors appears to be as crucial to midsummer debut success as Hollywood thinks.

Disney/Pixar’s “Finding Dory” won its third-straight weekend by taking in an estimated $41.9 million over the domestic holiday frame, topping the debuts of WB’s “The Legend of Tarzan” ($38.1 million) and Universal’s “The Purge: Election Year” ($30.8 million). Trailing all three was the underwhelming opening of Disney’s “The BFG” ($19.58 million), which had a reported production budget of $140 million.

So just where did “The BFG” go wrong?

The film, after all, received an A- CinemaScore from opening-day audiences and garnered a solid score of 66 on Metacritic — not quite in “Dory’s” company (Metascore: 77) but certainly a superior critical average than the “Purge” sequel (55) and “Tarzan” (43).

Yet there are other factors that foreshadowed why “The BFG” was relatively D.O.A. for the Fourth of July weekend. Here are a few.

1. The WTH? title

“The BFG” (short for “big, friendly giant”) was released by popular British writer Roald Dahl 34 years ago and has reportedly sold tens of millions of copies in the U.K. Yet in the States, “The BFG” doesn’t have quite the same name recognition as beloved Dahl tales like “Charlie and the Chocolate Factory,” “James and the Giant Peach” and “Matilda.” (Ask some American teenage fans of those last three titles about “The BFG,” as I did, and you may get nothing but blank stares.)

“The BFG,” as the fuzzy acronym of a main title, needed to RIP in the United States, even if meant going with something like “Big Giant.”

2. The Spielberg brand

The Spielberg name, contrary to some reports, is still highly relevant to many adult filmgoers; it continues to bestow a certain expectation of prestige cinema and storytelling quality among fans of such movies as the Oscar-nominated “Bridge of Spies” and “Lincoln.”

But to the under-16 set that a film like “The BFG” needs to appeal to massively? Frankly, such names as J.J. Abrams, Guillermo del Toro and Peter Jackson now create a buzzier expectation among kids. Spielberg remains a genius, but even the “genius” label ain’t necessarily bankable on an opening weekend during the summer — aka the season of “Sausage Party.”

3. Whither the kid-friendly stars?

If the names of the film and the director don’t exactly excite the kids, then surely a name that resonates with younger viewers is among the featured leads, no?

No.

The leading cast is replete with gifted and wonderful actors, from the Oscar-winning Mark Rylance (as the BFG) to Penelope Wilton to newcomer Ruby Barnhill (as young Sophie). And four superb talents — Jemaine Clement, Rafe Spall, Rebecca Hall and Bill Hader — also are in the mix. But there was no hedging of all-ages bets here by casting a well-known “Disney kid” — or an Andy Serkis. This wasn’t necessary a miss, just a casting calculation that didn’t add another element to the equation.

4. The box-office perils of motion-capture

For seemingly everyone not named James Cameron or Peter Jackson, filmmaking that is heavily reliant on multiple motion-capture (or “mo-cap”) performances can be risky business, given the high costs and sometimes tepid audience response — no matter how ingeniously gorgeous and inventive the spectacle.

For every smash like 2014’s “Dawn of the Planet of the Apes,” there can be a costly flop like 2013’s “Jack the Giant Slayer,” which grossed $65.2 million domestically on a reported $195 million budget; or 2011’s “Mars Needs Moms” (also from Disney), which grossed $21.4 million domestically on a $150 million budget.

Spielberg is one director who has succeeded with motion-capture in general, though: Smartly banking on the overseas popularity of the classic Herge cartoon character, Spielberg’s “Adventures of Tintin” made nearly 80 percent of its take overseas, to gross $374 million total.

Roald Dahl tales have been rendered beautifully in stop-motion animation in the past — “James and the Giant Peach” and “Fantastic Mr. Fox” are standouts — but that technology tends to run at a fraction of the cost of motion-capture budgets.

That said, we can hope that “BFG’s” visual brilliance will eventually gain greater audience appreciation on the industry’s all-important next-step acronym: the DVD.

Fun with numbers

— Over the full four-day holiday weekend, “Finding Dory” grossed $50.2 million, topping “Tarzan” ($45.6 million), “The Purge” sequel ($34.8 million) and “The BFG” ($22.3 million).

— “Finding Dory” has grossed $380.5 million domestically and is just about to pass the original, 2003’s “Finding Nemo,” when not adjusting for inflation.

— “Dory” still has an outside shot at becoming the biggest domestic animated film ever. The champion remains DreamWorks Animation’s “Shrek 2″ ($441.2 million, not adjusted for inflation).