It is a per year limit. Most H1-Bs return back to India within a year and a new person will be sent to fill in the same position next year.

That's why most people never get PR. The main reason is not to short charge the client, but to give chance to other workers in India, cause most companies pay them only $5k to $14k/per year back in India(That's the market rate in India). There is a rat race where people have to fight to fly to US or other western countries so that they can earn 10X more.