My dad is a landlord. He (through inheritances) owns 3 houses that he rents out. For one couple he did not increase the rent for decades. They were friends, they also took a bit of care for my grandmother who lived next door.
When my grandmother died, he rented out her house. A group of 4 Polish people moved in. He did not know them. They work in Belgium because the pay is better. He helped them out with getting official work permits. Noticed that the employer in Belgium was employing them illegally which meant that they were not covered by our social security system. He made a point of getting them a legal contract. Phoned the company, phoned their legal department. Their employer fired them because of my dad's actions, he got them a new job that payed better and was completely legal. (He was retired by then, he made this his hobby). He has some political connections. Employer's company was paid a visit by the government to check out the work permits.
The other house? Renter had trouble paying because she lost her job. He suspended her rent for a few months until she got employed again.
Whenever inflation kicks in, he gets moody. Do I increase rent yes or no? It is in the contract that he can. Sometimes he does, sometimes he doesn't.
He just likes people and people like him back. This is pretty normal for his generation in my experience. (Early babyboomers)