Death, taxes, and Erling Haaland's name on the scoresheet.
It's a rare commodity to have someone in your squad for whom goal scoring comes as naturally and instinctively as anything.
But that's exactly what Borussia Dortmund have got. It's no secret that Haaland is a freak of nature in front of goal and his numbers are simply frightening since his €20m arrival - yes, just €20m - to the Bundesliga last January.
The Norwegian has scored 37 goals in 37 games since arriving at Signal Iduna Park from RB Salzburg - for whom he notched 29 goals in 27 appearances.
So why, with all these goals from Haaland and a creative force around him, are Dortmund fifth in the league, ten points behind leaders Bayern and in danger of missing out on Champions League football next term?
Well, they're plagued with a seemingly incurable hopelessness at the back, costing them points, results and in the end trophies - and in the process costing Haaland a shot at true greatness in the footballing world.
While BVB boast the second best attack in the Bundesliga this campaign, their defensive record is the second worst in the top eight, conceding 26 in 18 matches - seven of those coming in their last three.
There was hope in December that the sacking of Lucien Favre after a shocking 5-1 defeat to Stuttgart followed by the interim appointment of Edin Terzic would turn things around for Dortmund. While BVB's style of play and chance creation has vastly improved since Terzic's arrival - proved by an increase in expected goals per game by around one - defensive issues are still very, very apparent.
While they were uncomfortable in a back three under Favre, Terzic's reintroduction of a back four seems to have left them looking confused and sloppy.
This was on show more than ever as Dortmund succumbed to a 4-2 defeat at the hands of rivals Borussia Monchengladbach, who subsequently replaced them in the Bundesliga's Champions League places.
What's worse is that all four goals were completely avoidable.
Lackadaisical marking from Manuel Akanji, unforgivable handling from Roman Burki, a lack of desire to close down from Mateu Morey and Julian Brandt, and a weak jump by Emre Can all led to the respective goals which undid the hard work done by Haaland in the first half.
BVB's previous match against Bayer Leverkusen also highlighted the backline's lack of awareness of their surroundings and positioning, eventually allowing 17-year old Florian Wirtz to steal an 80th minute winner in a 2-1 defeat.
Every team are going to lose games over the course of a season - that's a given. But these two examples of unconfident, shoddy and woeful defending are not one-offs for Dortmund. Defensive mistakes have been a feature for them all campaign, and it's left them looking unable win silverware and even at risk of finishing outside the top four - begging the question, is Haaland wasted at BVB?
While the striker is happy at Dortmund and is showcasing his glorious talent on a permanent basis for the side, it seems unlikely that he's going to get the opportunity to lift trophies while he's there - purely for the fact of what's behind him.
One thing is for sure, though - Haaland will always be amongst the goals. But, if he wants to earn the title of a true great and success story of the game by the time he retires, the Norwegian should think about silverware and not just the scoring charts.
Of course, all depends on how the striker himself defines success. If it is trophies as well as goals, then we may see him leave BVB for a true domestic and European competitor sooner rather than later.