If you find consecutive notes in ending serial sequence 1, 2, 3, and 5, would you keep the 5? Finding that 4 to fill that gap, would be next to impossible. Any value in keeping that 5?
not much value in keeping any consecutives, unless they are older notes OR a rare district or print run. With billions of notes normally printed for each district ... your great grandkids might not even see a gain on it. Its sad, but mostly true.
Ah yes, but billions are also shredded so who's to say which ones will really be scarce in 5 years after they've shredded the majority of the current design. Personally, the answer to OP's question depends on what series, denomination, and condition. For anything newer than 1996, I wouldn't even bother unless it was UNC or better, unless there was some other compelling reason to add value such as an error note or all 9's in the serial number.
I guess the question would be how much real demand there is, how many people are looking for 4 consecutive common notes?
My guess is, probably not many. I know that 10 or more consecutive sometimes gets certain people excited enough to pay a slight premium, but unless they're stars or a rare run or older notes or something, still not that much over face really. Somebody may want them I'm sure... but the demand probably isn't there to get anything over a very slight premium over face. If you're talking common notes I suspect it would have to reach the point that those notes period are relatively scarce in high condition... then having four consecutive serials will mean more. Probably take 2 or 3 generations for that to be especially significant though.