A country never stops wanting more investment, and once a country has accepted investment money, there are parties in both nations that are incentivized to continue the relationship.

If a country takes money from China, they will continue to want to take more money from China instead of switching to a less well known, more risky alternative.

Also, if a country reneges on their investors, why would investors in any other country want to invest in them? They've already shown a willingness to go back on their agreements.