it is probably something like : 1. go to upwork

2. find a 2-3 hours task (eg: scrape entire site [sitename].com, design a logo etc. etc.

3. give the same task to 5 different candidates

4. choose the best one

5. make profit and gain upwork cred

6. send a "thanks but we chose a different candidate" email to all the candidates

7. repeat

(edit:formatting)

edit2: you can even let candidate X make a code review on candidate Y.

step 8: automate the process and go public