The transition to socialism is always rough. When you make incursions into the market, it creates distortions in the market: capital flight, issues with supply & demand reacting back against your wage hikes and rent controls, etc.
You can respond to these distortions in one of two ways: (1) back off and compromise, or (2) push further, making further incursions into the market, to increasingly resolve the issues that your initial incursions made.
Of course your further incursions will cause further distortions. So you’ve either got to keep pushing all the way to a system not based on the market (socialism), you’ve got to abandon socialism entirely, or you try to maintain an unsustainable holding formation or mixture (European Social Democracy, the current situation in Venezuela). Applicable to the future of Greece.