Just unsure about the Freelance world

Examples

Lots proposals. How are we reassured that four proposals arent accepted for example on each project with four or more Freelancers doing the work and the best or a combined project selected with payment made for one or none?

There are no UK location jobs on this site. There are a few on a different Freelance site but its not an accepted UK way of working with the exception perhaps of Journalism and Photography and Acting.  

Freelance Jobs 
Motion graphics - Animated charts and graphics URGENT
FIXED PRICE
££
SEND PROPOSAL
China Manufacturing agent - Electrical, EL Panels
PER HOUR
££
SEND PROPOSAL
Help me upload PDF magazines to the Apple iTunes newsstand
FIXED PRICE
££
SEND PROPOSAL
Add Keywords & SEO my wordpress website
FIXED PRICE
££
SEND PROPOSAL
I need my logo redrawn as a scaleable vector
FIXED PRICE
££
SEND PROPOSAL
Creative Writer needed to write content for website
FIXED PRICE
£16
SEND PROPOSAL
Professional web page
FIXED PRICE
££
SEND PROPOSAL
Ebook writing
FIXED PRICE
£118
SEND PROPOSAL
Product photography - Pull-along toys,
FIXED PRICE
££
SEND PROPOSAL
Production Drawings
FIXED PRICE
££
SEND PROPOSAL
I need an explainer video / how to video for website
FIXED PRICE
£
SEND PROPOSAL
I need a designer for a brochure flyer PRE-FUNDEDURGENT
FIXED PRICE
£94
SEND PROPOSAL
I need someone to create a logo
FIXED PRICE
£20
SEND PROPOSAL
I need to cost out the design of a very simple ECard Website
FIXED PRICE
££
SEND PROPOSAL
Proofread (EN)
FIXED PRICE
££
SEND PROPOSAL
Customize pdf door catalogue. the job to be done within 20h URGENT
FIXED PRICE
£50
SEND PROPOSAL
Voiceover for website
FIXED PRICE
££
SEND PROPOSAL
ECard website design
FIXED PRICE
££
SEND PROPOSAL
Configuration of a Wordpress and Jomres based hotel bookin...
FIXED PRICE
£10
SEND PROPOSAL
I need a revamped LinkedIn Profile
FIXED PRICE
£8
SEND PROPOSAL
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