Many companies, especially start-ups, do erratic things, like hire someone and then lay them off weeks or months later even if they are doing a good job, because of restructuring, funding failures, etc. I've seen it happen many times.
If you relocate for a job, or give up a stable current job, or a number of other things, you're just essentially trusting the new company not to do this to you, and often it's completely blind trust and you have no way to know in advance if your trust is well-placed.
If they are willing to compensate you for a situation where they unexpectedly (not due to any cause by you, like poor performance or insubordination or something) throw you into unemployment, possibly in a new location where you lack a professional network to find the next job, or where you would not choose to stay apart for the job you took, it shows a willingness on their part to earn your trust.
It's extremely bizarre to me to hear someone characterize taking a new job by saying "I don't understand what the risk is." It's a huge, huge risk every time that the new place is going to treat you badly and that you could not have seen it ahead of time because they didn't emit red flags during the hiring process. And many ways of them erratically treating you badly results in you suddenly having no income or insurance and needing to figure out what to do -- a situation that should absolutely never be financed out of your personal savings (though, often it is because people rarely negotiate adequate severance).
Perhaps you've been very lucky with working for good companies and just haven't experienced how prevalent this is.