Lets say you wired this new custom home an you had a 100 foot run to a range or oven an you have 3 pieces of cable that would work providing you use 2 splice boxes , now one year later when the warranty has run out you get a call from happy home owner my range doesn't work maybe it's the circuit breaker can you come out for a service call an check this please.
You arrive with a smile on your face check a few things then take a look under the crawl space an you see one of the splice boxes you installed a year ago an find that one connection had burned through the connection for what ever reason , so you fix the problem an present happy home owner with a bill for $190.00 which he pays.
Now two months later you get another call from unhappy home owner my range has stopped working again , you pay him another visit an check box #1 everything is fine so now you remember adding a second box an you proceed to checking it's connection an to your surprise that connection also had burned through it's connection for what ever reason , now you find that you don't have the materials to make the repair at splice box #2 an have to run to supply house or home depot to get what you need for the repair and then present unhappy home owner another bill but for $235.00 this time , an he looks at you an says why do I have to pay you again for what you said you repaired the last trip , now because your an honest person you say to him I used two junction splice boxes under the crawl to use up some left over wire when we wired the house from the start , unhappy home owner is standing there steaming mad with eye balls rolling around in his head an popping out.
All you had to do from the start is take a whole run from point A to Point B
End of story