Breath is the natural reality and is coming and going from the time person takes birth till his/her death. If you start reiterating/recalling any name/image in your meditation, after some time that name/image becomes prominent and person's mind in focused on that object.
This means mind can be focused by concentrating on breath, name or any image. In most of the cases focusing on later would be easier but to go beyond just focusing the mind (the stage next to 'samadhi'/meditation is called 'Panyaa'), you have to work with the naturally appearing reality (like a breath) and not with any name/imagage (artifically created object).
Hope it answers your question :)
May all be Happy!!!
Ashu
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Regards,
Ashish