Why do some critics say that the miranda rule "puts criminals back on the street"?

The Miranda Rule refers to the fact that police officials must read an accused person of their rights (like the right to remain silent and right to an attorney). If an officer of the law fails to do this, the case will be thrown out by the court.

In this case, one could see how people would critique this rule. This rule makes it so that if an individual commits a crime and is caught they could be let free if their Miranda rights are not read to them. This is the case with Miranda (the man from Miranda v. Arizona that establishes this law). He confessed his guilt after hours of interrogation with police but his case was thrown out, as his lawyer argued that he was unaware of his rights.