Cable management is complex. There are cost involved, as well as scheduling, and you have to be in top of it. Cable management has challenges, but there are solutions: setting parameters lets you think about ordering on time, managing the cost and the length. Maintaining these parameters allow you to have the optimum amounts of cable, not too much nor too little.
If you can look at your goals you have the flexibility to order the cables on time and the speed to adjust an order to be sure you have everything when construction starts. Joop says you must manage the cables in conjunction with the standard reel length. You don't want to just "slice" cable off any reel, you must manage the resources to find the optimal use of all ordered cable reels.