Why do serious machine shops often replace their Haas CNC machines when they grow?

I have an idea this was not quite fair. No way the hp requirements of that cut exceeded the hp of the machine. My 15 hp fadal could do that cut. Proly a 5 hp machine could. Ahm no 'spert, but vmc's have a way of detecting a crash condition, and it looks like that's what was happening here. If he came in at, say, 60 ipm, and then *ramped up to 120 ipm*, I'll bet good bucks that the Haas would not have alarmed out.
If this is the case, one could arger that the Haas was a *safer* machine, and that you just have to work around this a bit, from a production pov, but once worked around, will still have better "crash protection".
I don't think anyone, not even Haas, would debate that the makino is a "better" machine. It all boils down what you actually require, and bang-fer-yer-buck.
Also, I don't think ramping up is such a bad idea, anyway, altho mebbe unnecessary once a program has been proved out, for full production.

It was a fair test. The way Haas calculates HP isn't really honest. I learned this when using a Haas Mini Mill in Qualcomm's prototype machine shop. Until I dramatically lowered the spindle speed, I couldn't take a decent depth of cut with a 1/2 inch end mill in 6061. I think "tiny d" helped me out on this years ago when posted about it and he suggested lowering the spindle speed. Bottom line is that the way Haas rates HP is bullshit and that their machines don't have the HP that the Japanese machines that cost more do.
***** If i cut that aluminum piece in the vf2 I ran 3-4 years ago it would of ripped thru that aluminum like butter.
id like to see his spindle load setting that caused it to stop. Ive tried to use spindle load on the haas, and i believe I posted what I did in this group, and the results showing its basically useless. it would max out the spindle load simply ramping up the rpm and stop.
But in all fairness, the makino blows away the haas and price fairly relects that. But damn if that vf2 i ran wouldnt of handled aluminum. there's more going on here. I bet most anybody could get that to cut good. Turn off the damn spindle load safety, it doesnt work for shit. Haas's are cheap. A bunch of shit on haas's are basically fake. I tried 3d cutter comp...didn't work. Calling haas they said its not fully implemented. WTF does that mean? It means it;s not a makino, and is a lot less in price. But not all shops are in a position to buy a hopped up makino, nor is it economically smart for them. Just don't think buying the best haas puts you at a level that makino was at. Look at how slow it rapided over, it's a toy compared to that badass makino.

Let's see what the approximate Horsepower of that cut is.
Material Removal Rate MRR = WOC X DOC X FEED RATE
.500" X 1.500" X 120 IPM = 90 cu.in. MRR
HP = Unit HP (.25 for Alum.) X MRR
.25 X 90 = 22.5 HP
Now the Haas VM3 specs say the max torque is 90 ft-lb @ 2000 RPM
Torque X RPM / 5252 = HP
So 90 X 2000 / 5252 = 34.3 HP
Lower the RPM from 3,000 to 2,000 and the Haas should theoretically be able to do the cut.