Learning new phrases all the time

Scenario:  A friend/colleague is explaining the need to protect one's business interests when multiple companies are involved in a potential business deal with one of my clients.  He explains in rapid-fire Hebrew how each company will present their own products and services to my client in as positive light as possible, and will usually also try to position themselves as the prime point of contact... even at the cost of making the other 'partners' in the deal (including me) look incompetent.

At the end of this helpful little business lesson he stresses the importance of always being physically present for any and all discussions with my client... even if the topics being discussed aren't directly related to my part of the deal. 

When I asked why, he looked bewildered at the stupidity of my question and practically shouted: "Acheret hashutafim shelcha ya'asoo l'cha peepee b'cafay!" (translation: 'Otherwise your partners will pee in your coffee!').

After I stopped laughing and got up off the floor, I realized that while you probably won't hear that particular phrase in a typical American MBA curriculum, and an accredited online MBA school might worry about losing their accreditation if they tried teaching it to students, here in Israel’s no-holds-barred business environment, it might be wise to include it.

[Update:  I've been thinking about this funny phrase all day, and it occurs to me that the equivalent English expression to having someone 'pee in your coffee' is having someone 'stab you in the back'. Upon reflection, I think I prefer the non-lethal, Hebrew idiom for betrayal.]