I am make a test with my shop in Contabo, very cheap plan, €3 only! Then come the Black Friday and PUM, site down, all red in uptime graph. I send apology email for my 12 customers, very professional, "we are experience technical difficulty"
The support from Contabo say "you exceed resource limit" and I think WOW, I am viral, we make a test and is very good, my marketing is rocket
But then I check the log... twelve simultaneous visitors. Twelve! Not twelve thousand. Twelve. My $3 plan die with twelve people. Is very good, no?
Now I am upgrade for Hetzner €5 plan, we see if support THIRTEEN visitors. What is your acceptable downtime threshold, friends? For me, 100% uptime or I send more apology email.