Physical,spiritual,mental,financial,family,friends,etc. 

Maybe, it is some sort of mental block, or mental hangup that you cannot understand.

Other ideas I've had are perhaps less conventional, such as offering English language classes, providing info for tenants to access free counseling if they have marital/drug/mental health issues, and even hiring tenants to make repairs if they are qualified to do the work and trustworthy individuals.

The sad thing is that most people are so negative and live in a cynical, defeatist mentality they will never succeed in anything that is not a job. 

I'm trying to actively take steps towards real estate investing, but there is a lot of mental endurance that I need to break through - perhaps cultivate the hunger or curiosity for real estate.

It’s that old slumlord mentality.

I think there would have been more mental anguish and time involved that wouldn't be worth it.

I have spent a good amount of time with some larger syndicators understanding their capital strategies (no one on BP) and I would say that the thought is that the larger investors will eventually get tapped out on their allocation to you, will get tied up in other investments in a downturn and/or will find other investments at the wrong time for you and thus the mentality is to build that list of repeat business and keep doing deals.

When you are dealing with someone who leaves feces around on the ground, it is someone with mental illness.

Like these others, I have little compassion as you need to pay your own bills, accept responsibility for your own choices, and not have this victim mentality.