"a flash in the pan"
something or someone with a showy and popular or successful beginning but fails to deliver any lasting success or value
Related words and phrases:
Two colleagues are talking ...
Colleague 1: Aren't you worried about our competitor's new product? The launch was very showy and sales have skyrocketed. It seems like an extremely popular device.
Colleague 2: Let's see if sales continue going strong or if their new gadget is just a flash in the pan before we react.
Two friends are talking ...
Friend 1: Looks like with this new player that our team has a really good chance to win the championship this year.
Friend 2: It has only been a couple of games. Sure, the new player is marvelous and has scored a lot of goals but will her stellar performance be permanent?
Friend 1: You think she is a flash in the pan?
Friend 2: Time will tell.
Being a flash in the pan, the singing group had one hit and then was never heard from again.
1) If indeed the finance minister is not just a flash in the pan, or not mere sound and fury signifying nothing ...
2) ... will stand the test of time or prove to be just a flash in the pan.
3) ... thought it wouldn't last. But he wasn't just a flash in the pan -- it was serious.
4) ... to make sure that their income is stable and not just a flash in the pan.
5) That became a nine day wonder or a flash in the pan as nothing came out of it.
6) ... continued to argue that the seeming currency war victory might be a flash in the pan unless the central bank allows the market to fully determine the exchange rate.
7) Sometimes they're a flash in the pan, doing limited damage. But sometimes they arrive at the same historical moment as ...
8) ... culture of success that allows them to maintain momentum. But a flash in the pan is no basis for a long-range strategy.
9) And it can't be a flash in the pan and then abandoned later on; it has to be sustained.
10) Rather than a flash in the pan it's a new emergence of a sub-sector.
11) ... nothing again has been heard of the scheme -- was it a flash in the pan?
12) Innovation can easily become a flash in the pan moment, rather than a long-term strategy to safeguard the organisation into the future, ...
13) ... scored 45 million viewers and proved that the series wasn't a flash in the pan, but rather the new face of television.
14) ... armed with a number of records that proves he's not a flash in the pan, and if he persists, he should become a household name in earnest.
15) And success must breed success. Else, it's just a flash in the pan.
16) It's so very important and can be the difference between a flash in the pan and a lasting life change.
17) It's not a one-off, he's not a flash in the pan.
18) ... more worrying is when the iPhone 7 boom is also just a flash in the pan, what can Apple rely on to hit new peaks?
19) I think what this proved is this is not a flash in the pan. We're not going into next year as heavy-duty underdogs.
20) ... to continuously advance if it's to become more than just a flash in the pan.