Which site are you using if I may ask? And what is your idea of short time in this context?
What I see is that quality of loans go down as a platform scale and I am lucky to be with this platform from the start. So my cohort is made up of mostly early adopters. I am year in my portfolio with 0 defaulted loans and 1 late payment (I feel like this loan will default during the lifetime).
My strategy is to invest to nonconsumer debt (no car loans, no holiday or Christmas presents loans or loan refinancing). I am investing in loans with disclosed profession (investing in IT professionals, govt workers, school teachers...) and with disclosed loan history (aiming to people with 0 debt). I want the loans to be paid in 3 or 4 years. I do break my rules for about 5% of portfolio that goes to riskier loans, this is where I get majority of my yield, otherwise my yield would be like 4 or 5% instead of 7 - 8%.
I guess this strategy is not applicable in US or UK, where is normal to have some debt (there is/was very different debt culture in most EU), and even here is still harder to discover these good loans, so I basically stopped investing in there.
Next year I want to start experimenting with b2b loans for unpaid invoices (business sell their new invoices with terms like NET30 or NET90 to boost their cashflow).