1. Loss of precision: The use of a lesser precision variable for a temp variable can lead to loss of precision which leads to bugs.
Ex: Using a Integer variable to store the result of a calculation that includes a higher precision like float or double. Even in langauages like java by explicitly typecasting(coders mistake).
2. Value out of bound: Similar to the first mistake but occurs in arrays and strings. Can mainly lead to rendering mistakes.
Ex:While using the last few characters of a string or last few values of an array.
3. Multiple inputs: The temporary variable value can get overwritten by incorrect code even before its value is used.
Ex: Status being changed even before the code required to be executed in previous status completes execution.4. Excessive memory usage:The excessive use of temporary variables can have an impact on the memory usage of the program.
Ex:Using temp variables even when they are not absolutely needed.
5. No exception handling ( Like Null value, negative value) :The temporary variables can behave in weird ways if various exceptional cases are not anticipated and guarded against.
Ex:Not guarding against storing negative values in temp variables later used as array index etc.