On a night out, three little words can have a huge impact on whether or not there's a happy ending. "Here's my number" or "You wanna stay?" usually represent a good night's work; hearing "Not tonight lads" or "I'll call you" has the opposite effect.
In match reports, three words can also sum up a day's work. On Saturday, Robin van Persie and Dimitar Berbatov were both "hat-trick heroes," one of the rare expressions in football that has no negative connotations, but one which few get the opportunity to put their names to.
Far more common to players are the three other little words at the very end of a report which undermines any name that follows -- "subs not used." In real terms, the word "useless" could be used instead for a more accurate picture of how the player was thought of by the manager on that particular day.
Maybe they're a fan favourite or tell a few jokes in the dressing-room, but, at no point during the 90 minutes of the game did the manager feel they could make a blind bit of difference to the outcome despite the fluctuating fortunes that go with almost every match.
In the Premier League on Saturday, mostly from Manchester City, there was a team worth of subs not used (SNUs) that would make a realistic case for staying up.
In goal, Shay Given; at the back, Pablo Zabaleta, Joleon Lescott, Phil Jagielka, Vedran Corluka; a midfield of James Milner, Patrick Vieira, James McCarthy and Joe Cole; leading the line could be Jonathan Walters and Nicola Zigic. And that's not including the likes of Paul Scholes, Kieran Gibbs or Nicolas Bendtner, who didn't appear.
For Given, this was the 24th such occasion this season and, despite his reputation as being among the game's nicest men, he would not be human if he watched Joe Hart push the ball into Darren Bent's path to cost Manchester City the match and think to himself: "I'd have done better than that."
It's rare for the Premier League superstar to have much in common with the Sunday morning barely-rising star, but, in the SNU brigade, the thought of 'why am I wasting my time?' shows no discrimination.
There are two categories of those who watch and wonder. The first is the one who wants the team to win, just not too well, and for the person playing in their position to have a bad game, get sent off or be injured (nothing serious of course, just for one or two games to give the bench-warmer a chance).
The second category is those who just want the team to do well, who cheer them out of the dressing-room and back in afterwards (and mean it) and be genuinely happy if the person playing in their position is Man of the Match. This category can be bracketed under the headline: Liars.
While it's rare, and a little sad, for somebody to want the team to lose simply because they're not playing, the manner of the desired victory varies wildly depending on position. Strikers on the bench will want the team to win 1-0 courtesy of a scruffy goal which owed everything to the opposition's incompetence and nothing to the predatory instinct of the attacker.
Defenders and goalkeepers desire a thriller, not to lift the abject boredom that goes with all the pointless warming-up but, while keeping the manager happy with three points, it generally means bad defending or goalkeeping has contributed to the excitement. A 7-6 victory would be just about perfect.
At least when they are introduced, goalkeepers may have a moment of drama to instantly make themselves a hero by saving a penalty given away by the first-choice stopper who has just been sent off.
The potential for this to happen is a small crumb of comfort for what is undoubtedly the worst position on the pitch to be second choice for. Not too far behind that, however, comes those directly in front of the 'keeper.
There are thousands of scenarios which can happen in a game, but very few end with the manager pondering, talking to his assistants and then finally deciding that the only way that they will be able to change the game is by bringing on a new centre-half.
At 1-0 down, a striker is usually summoned from the bench and given instructions that, in the professional game, usually leave them with the expression of a lost driver desperate for directions. (To prove they were listening it is then essential to run very fast on to the pitch, shout and point before delivering news of the new formation with Ted Rogers-style hand movements from 3-2-1).
At 1-0, another centre-half might be able to win a few headers, although that's balanced off by the danger of them crashing into those who are already there or giving the ball away while trying to impress instead of just hoofing it up the field. The one positive for the SNUs is the lack of guilt by association. At half-time on Saturday, neither Alex McLeish nor Roberto Martinez would have been killed in the stampede if they'd offered players the chance to come on at Old Trafford or the Emirates just to be on the end of a hiding.
Instead, those who didn't appear did their post-match sprints in an empty stadium, but with renewed enthusiasm because they might get a chance next week. Sometimes, "not tonight lads" can be a blessing.