Self-referencing systems have nasty self-reinforcing feedback cycles and it cuts both ways - both positive and negative. Without going into things like invariance, strange loops, recursion, self-similarity etc, essentially there is no difference between the product and the payment for financial institutions (unlike a steel maker who sells steel and gets paid in cash) - this is what I meant by self-reference. A loan can be siphoned off by faking a borrower but you can’t siphon off steel with the same ease.
Similarly, credit and Money are similar but they are not the same but are used interchangeably so often. Then there is the interconnectedness of the financial institutions and systemic risks which again arise out of self-reference and recursion. Then we have things like derivatives. This sort of self-references breeds unpredictable complexity. Where there is self-reference, there is complexity - the human consciousness is a prime example of this. For more on this topic if you are interested, I suggest Godel, Escher, Bach by Douglas Hofstadter
This is the prime cause for boom and bust cycles. I am not saying avoid financial completely but avoid them for the most part. Post a recession these are in the goldilocks zone where there are rate cuts, high growth, low inflation, economic stability - the works. I wouldn’t mind being in during that time but any other time, the systemic risks are always on the rise owing to poor lending standards which invariably creep up after the goldilocks economy - as economy overheats, rate cuts dont spur growth, inflation rises as does bad debt and with it goes down the debt servicing capacity and then the painful deleveraging (which is where we are now). If you are interested in this, do read Ray Dalio’s Big Debt Crises. Hope I managed to convey my thought-process.