When the facts have not changed between the time of the original speech and the time it is reported, then the choice of tense does not really matter. When the original statement is only in the recent past, then people are likely to use the present tense in the reported speech. For example:
Bob takes a big bite of food and mumbles something unclear.
Anne: "What did he say?"
Jose: "He said he loves potatoes."
When the reported speech occurs very soon after the original statement, even the verb "to say" may be in present tense, so Jose's response above may be:
Jose: "He says he loves potatoes."
However, the past tense might be more appropriate than the present tense when the original statement is no longer valid or applicable at the time it is reported. For example:
Anne: "Bob's car won't start."
Jose: "That's strange. Yesterday he said that it was working well."
If Jose had used the present tense in the reported speech, it might sound like he was accusing Bob of lying. The past tense instead implies that Bob's situation may have changed.
The past tense can also be used to emphasize uncertainty as to whether the reported speech is still valid or applicable.
Anne: "What dessert would Bob like?"
Jose: "He said he liked ice cream, but it has been five years since we had that conversation."
Here Jose might use the past tense in the reported speech simply to emphasize that things may have changed since the time of the original statement.