I got a taste of this in my high school honors biology class. I decided to do a survey of redwing blackbirds in my town. I had a great time, there was a cemetery across the street from my house with a big pond, where 6-8 males hung out. I was excited when later in the season several females also arrived and took up residence.
I eagerly wrote up my results in a paper. I thought I did "A" level work but was distressed when the teacher gave me B- or C+. She said "My husband and I are birdwatchers who have published papers on redwing mating habits in the area, and we haven't seen any females this year. Neither did one of your classmates who watched redwings in her neighborhood." While she did not directly in writing accuse me of fraud, she strongly implied it.
I told her to grab her binoculars and hang out at the cemetery one morning. She declined, as she was a published authority and didn't need to actually observe with her own eyes. IIRC I had photos but they were from faraway with a Kodak Instamatic (this was the mid-'80s), so she didn't accept those as evidence.
I often wonder if my life would have gone in a different direction if I had a science teacher who actually followed the scientific method of direct observation! It didn't come easy to me, but I was very interested in science before this showed me clearly that science is just another human endeavor, replete with bias, ego, horseshit, perverse incentives, and gatekeeping.