For my side project website (see my profile), I started to implement PayPal and got seriously confused with the documentation and process (I'm not a professional developer). Mid-process I actually didn't even know if I was even dealing with PayPal or Braintree anymore. Then magically I received a package in the mail from Moneris. They shipped me a stack of those carbon-copy paper credit card slips and machine (that cha-chunk sound)... for my website. This was like 3 years ago.
I asked my professional dev friend what the heck was going on and he told me to use Stripe. Never heard of Stripe before that. Friend also told me his revenue was frozen for weeks/months by PayPal for his projects. A weekend later, I was done implementing Stripe.
My partner insisted I use PayPal because that's what everyone recognized/used, but I flat out refused after implementing Stripe.