Data recovery software is an essential part of recuing data when it has become inaccessible or cannot be viewed or interpreted corrctly because of certain types of corruption. But there is an essential statement to be used viewed when using any data recovery software "do so at your own risk !" .
Many of the problems faced when a hard drive start to degrade can be made still worse by using software which with the best will in the world cannot recover data without specific hardware control to ensure that the sectors of data that can be recovered and imaged to a donor drive are done so before the drie fails completely and an expensive rebuild is needed.
Software is a cost effective answer if you do not value your data or are willing to take the "gamble" but be sure you understand the odds when asking software controlled by an operating system to access a degrading drive, many times it can result in a totally stripped platter surface which even our rebuild skills and specialist hardware cannot get around so be sure you know what you are letting yourself in for.
I have not included my email or phone number to ensure this is not seen as an unbiased comment, it is a general comment about making the judgement about the condition of your data before using software data recovery .

I hope this helps, ..... and of course I accept how many times just software is needed for certain types of data recovery.