If it happens once, it could be put down to a slip.
If it happens twice, it might be a blip.
Three times, and you’re really starting to worry.
But four times would indicate a concerning issue.
So just why have Saints surrendered late leads in games against Bath, Leicester, Wasps and Saracens during the past two months?
Could it be that the required mental strength is missing?
Or is it an accumulation of pressure? The weight of not winning sitting on the shoulders of the men tasked with taking the final step over the line to victory.
“It’s all different things and I suppose it’s a little bit of that (mentality), but there’s certain things we can do better,” said Saints boss Jim Mallinder.
“It’s that mindset of when we need to keep the ball, keeping it, and when we need to be positive and continue to do the same things that worked during the first 65 minutes, we do that.”
During the 2013/14 season, Saints snatched victory from the jaws of defeat on several occasions.
They concluded the campaign by coming back from behind to beat Bath in the Amlin Challenge Cup final and recovering against Leicester and Saracens to seal their first Premiership title in dramatic fashion.
So is it just that the winning habit has started to elude Saints in recent seasons, piling more expectation on the players?
“I think it is that - without a doubt,” Mallinder said.
“A lot of the players are still the same players. The players who are on the field are experienced and it’s hard to put your finger on one particular area where it went wrong.”
Saints simply have to rediscover the winning habit in the final two matches though.
Mallinder’s men currently sit sixth in the Aviva Premiership standings and face Exeter at Sandy Park on Saturday before a final-day home fixture against Harlequins.
One worrying statistic for Saints is that they have only won one of their 10 matches against the other sides in the league’s top seven.
And both second-placed Exeter, who Saints beat at home back in September, and seventh-placed Harlequins fit into that category.
“We need a win,” Mallinder said.
“We’ve been frustrated because we’ve played quite well over the past few weeks against some of the top teams.
“We’ve put in some good performances, played some good rugby, scored some excellent tries, but not won.
“The last 10 minutes in each game have been frustrating all for different reasons.
“But it’s happened, and we’ve worked hard off the field to rectify some of those problems.
“We’ll go down to Exeter knowing it will be a difficult game, a tough place to play, but we’re in confident mood.”
Sandy Park has not been a happy hunting ground for Saints in recent seasons.
Mallinder’s men have not won there since Stephen Myler slotted a last-gasp conversion to seal a 17-16 success in February 2014.
“They’re a good side, they play good, attacking rugby from one to 15, they fill the field, like to move the ball around and score a lot of tries,” Mallinder said.
“They’re a very dangerous team so we’re really going to have our work cut out defensively to close down their attacking options.
“We’ve got to make sure we go with the attacking intent we’ve had recently but not turn it into a game of sevens.”