I went in for a coffee at the cafe. While the serv...

I went in for a coffee at the cafe. While the service was friendly and helpful, the actual coffee was undrinkable. They had burnt the gounds terribly. My guess would be that they don't rinse out and scrub the portafilter and/or associated parts after every shot. You need to, otherwise grounds from the previous shot get hit with hot high pressure water more than once resulting in a coffee that tastes very burnt. It's an all too common mistake in smaller shops unfortunately.