Most of the sanctions are whac-a-mole game played by the West (mostly by USA): as soon as one of the peripheral countries starts developing its economy, gains more wealth, starts to produce something the competes with products of Western companies, or attempts to avoid use of USD (because it allows immense enrichment of USA simply by printing it in whatever quantities), soon there starts:

- firstly, media attack ("they're dictatorship!", "they're genociding someone", etc), preparing population for stricter measures

- secondly, color revolution, which, if successful, puts puppet malleable government in power, and makes the country ultra-poor (most of the countries, where color revolutions staged by US/West succeeded, became significantly poorer)

- if color revolution didn't work, there's always an option to just bomb the country, because it's always ignored if all the international treaties and laws are ignored if USA or Israel bomb any other nation.