How check funds working for expenditures transfer from one project to another

Hello

when i perform the cost transfer functionnality in project costing from a project to another project with insufficient budget the system is Nevertheless creating distibuted line in project provider and nothing for the project receiver ?

Why the system is not bloking the transfer for insufficient budget right after cliking on transfer functionality ? instead of creating distribtion line in the project source and no line for the project receiver ?

Thanks for your precious help
Younes