[Backed Up] Freelancer.com stole from me and ruined my life
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web.archive.org
They survive by making you work for cheap when you enter the platform (kind of unwritten rule to earn "reputation") but once you start commanding better fees they will kick you out under any pretext - they know professionals with good portfolios are going to leave the platform anyway.
Freelance marketplaces are a race to bottom. They have a deleterious effect on your career turning you into a low-fee/shitty-client magnet.
It's mostly networking and word of mouth.