Because you and others are just looking at one litter at a time and not the whole package
I bought one young female in Germany - paid to have her titled and koered and bred...she came over empty. I lost the stud fee. I finished her titles here...along the way she ingested a foreign object and had surgery....she was bred once by surgical AI and came up empty. She was shown, trialed and koered. She was bred to a highly titled, well bred import. She had one normal pup and 2 dwarfs. At 2 days, one pup was not doing well...that pup went to the ER, was given blood transfusions, and tube fed...it ended up a dwarf. Spayed and gave away female...Spent and lost nearly $10K on this female.
Bought another one - had several empty breedings - all vet work still done and 3 litters....then got an infection being bred and was spayed....so those litters helped fill in the money pit a bit, but still cost money to produce.
Bought frozen semen in Europe....have stored it over 10 years at over $100 per year. Have done 4 surgical AIs with 3 females and 3 different vets...never had a puppy. Loss so far - probably close to $9k
OFAs and/or 'a' stamps on every dog I own that I bred or even brought over. With fees and transfer to film from DVDs - average $600 per dog...
Have done several live breedings with no pups....losses for vet testing, stud fees, , lost time from work, hotels, gas etc.
Bought $40K Silverado - put 250K miles on it doing dogs....got 2500 for it at trade in 6 years later.
Dog food is not grocery store brand but top of line...training fees, club fees, travel time, show and koer fees.....do not want to begin to add up. Pups wormed regularly from 3 weeks to when they leave - raised on ceral, goats milk, raw ground meat, yogurt from 3 weeks on, then to kibble. All paperwork done with AKC before pups are 6 weeks old and papers in hand ready to be transferred to new owners.
BYB - get cheap newspaper dog or even ok bred pup or two...let it grow up, feed Iams or Pedigree or Old Roy....female comes in heat, breeds to own male - no OFAs, no blood work, no travel, no time off work to do breeding...no training fees, no show and trial expenses....if pups are lucky, they get shots and maybe a worming maybe even from a vet instead of owner doing it themselves with supplies from Tractor Supply....
And that is just a quick and dirty skimming over summary....
Csabre Sch1, Hexe Sch2, Bengal, Komet, Kyra, Kira & Kougar v Wolfstraum ~ Ziberia BH ~ Danger Sch1 RH SAR ~ ATB~ Kougar Sch3, Kyra Sch3, Cito Sch2, Alice Sch1, Kelsey CD, Ret ~ Basha Sch3, Fenja Sch3