My first film camera was a Minolta Maxxum 5. It was fully automatic. Focus, exposure, film advance. I loved it, but I wanted more. I wanted to be in more control. So I did some research and taught myself the ins and outs of fully manual film cameras. That brought me to my first manual SLR, the Ricoh KR-5.
With a maximum shutter speed of 1/500, a broken light meter, and a 50mm lens, I decided to purchase my first real black and white negative film. Previously I was using Kodaks BW100CN which was a black and white film that could be developed as color in the usual c-41 fashion. I decided to go with the classic Kodak Tmaxx 400 black and white negative film.
There was a perfect opportunity to test my new gear. It was the third year of the now annual and famous NYC Pillow Fight. I had gone the previous two years, first taking a digital point and shoot, then my Minolta, and then my Ricoh. I shot 2 rolls of 36 exposures. 72 frames of film. I went back to my home in New Jersey and brought my film to the same place I had always taken my film. Due to price and convenience, that place was Walmart. I gave them plenty of days to process since I knew it had to go to the lab and not just through their '1 hour photo'. I went to pick up my rolls, excited and hopeful.
They had processed my rolls as color, effectively wiping all 72 frames from existence. As if they never happened. I will never know how I did, or what those photos looked like. Needless to say, I never went back to get my photos processed at Walmart.
One famous story that falls under this category is the tragic story of the destruction of 3 out of 4 rolls of Robert Capas photographs taken during the D-Day invasion. Only 11 frames survived due to a technician's failure to take the films out of the drying rack in time.
Moral of the story, trust your lab. Create a relationship with the people that you hand over your film to. Feel confident that they know what they're doing and that you can trust them with your hard work. Never again will I use a 1 hour photo drop off in a big chain store to handle my film ever again. Live and learn.