That really depends on the situation and without knowing the details, that's pretty presumptuous.
I had over a week of back and forth getting my last car because I have bad credit and had to jump through all sorts of hoops to get the loan approved. First they said that they thought they could get me approved on my own, I went through the paperwork for that and then they came back saying that they could not.
Then I got my mom to co-sign, that went to the banks and we expected it would be fine and that got rejected as well. She had to contact a credit bureau to get her credit history and found out that it was years and years out of date. They wouldn't approved to co-sign not because she had too much credit used, but rather because multiple old, paid loans (a mortgage, multiple cars, other lines) were still showing as "available credit" because they had been paid in full and never taken off her record. The cumulative total was close to $2M (with a very small percentage actually used) and they bank denied that on the grounds that with that based on that info she could in theory accumulate $2M in debt overnight by borrowing against all this old credit.
Finally, I ended up getting both my parents to co-sign just to get it done with, the process to get the credit history cleared was going to take too long, my old car's engine had exploded and I had an hour commute to work so I had to get it done before the dealership stopped letting me use the loaner.
Even with the credit fully approved though, there was still another hurdle, and again it was the bank and not the dealership standing in the way. In Canada, our banking system is very much dominated by five major banks. I know that there are big national banks in the US as well but from what I've seen there are also a lot of different players in the banking industry from state to state. We have much less of that difference from province to province with the big 5 dominating all over the country and you see much less of the more regional banks. Anyway, I do not bank with one of them, I actually have my banking done through a system run by one of the biggest grocery chains in Canada, who have pavilions setup in some of their stores for limited customer support but they do not have traditional tellers at all, everything is online.
That last hurdle that I had was that the financing was being done by one of the big 5 banks and they, in probably a joint effort of ignorance and an attempt at keeping their hold on the market while struggling to adapt to a tech driven society, refused to accept my banking info that I provided in order to setup my automatic payments. All they needed was the account information which a void cheque perfectly provides, but they wouldn't accept that. Thankfully, my online banking system also has an option to printout a letter with my banking info and a statement from the bank guaranteeing the info and a field for me to sign. but they wouldn't accept that either. The only thing that they would accept is a hand written for signed by a bank teller. That's the way that they provide that info for their customers, so it's the only way they were willing to accept it as well. Now, this may sound somewhat reasonable, you have a person guaranteeing the info is correct, instead of a machine spitting it out, but the issue there is that those machines don't really make mistakes in that sort of situation. Maybe the system can fail at times and be unavailable, but if you log into online banking and get in, you are getting your account info, it's not going to misread a number and write it down incorrectly. Tellers on the other hand do that fairly often. My dad runs a payroll company and almost every single time that banking info provided for direct deposit is wrong, it's because it was written down incorrectly and often times that the teller. He can't recall a time that one from an online banking system was ever wrong. This really seems to come down to them not wanting to deal with this other bank. They offer limited services but by doing so charge no regular account fees and pay more interest than the regular banks and i think it scares the shit out of them.
But anyway, now I'm off topic just complaining about banks. In the end, after much debate, we finally got that form approved despite the argument from the bank, but when it was all said and done, it was over a full week of me going to the dealership everyday to finally get this done. The dealership was nothing but helpful. They pushed the bank to accept my information when they didn't want to, they gave me a loaner for the week while the whole situation was ongoing, and they were very flexible on the price and we managed to talk them down quite a bit on the already discounted price for the end of year, on the lot vehicle.
TL;DR: There are many reasons that a vehicle purchase can be delayed and many of them are not the fault of the dealership. OPs dealership may well have been shady, or the week of paperwork could be entirely due to banks being stubborn idiots and not reflective of the dealership at all.