I’m with @hanshuber16. You can’t really apply the 80/20 principle on Fiverr. There are too many variables which you can not account for.
Say you have 5 gigs and realize that 80% of your orders come from just one. In this case, you could decide to up prices, giveaway free extras, or replicate that gig somewhere else to try and increase profits. Then though, the Fiverr search algorithm could suddenly kill exposure to that gig by throwing it out of the search.
Alternatively, a buyer could use chargebacks or repeated cancellation request to try and sabotage your success. In short, several things could go wrong.
That aside, earlier this year, I did discover a way to use Fiverr to predict the price of Bitcoin!
I realized that in advance of significant Bitcoin price rises, I start getting several spam messages from people I term ‘Fiverr Bitcoin Beggars’ who all ask me to sell them some Bitcon or try and lure me into a Bitcoin scam of some kind.
As Bitcoin prices do rise shortly after Bitcoin begging on Fiverr starts, I realized that I could use spam messages as an indicator that I should buy Bitcoin myself. I also illustrated this with the following graph:
I posted this in another forum in March. Since then, the Bitcoin price has almost doubled, proving my hypothesis in the process!
In this case, divining trends using Fiverr gig behavior is possible. In practice though, there are a lot of variables to be taken into account and everything at some point still becomes a game of chance.