A common problem in writing is deciding on whether to use active or passive voice. There is a general tradition in scientific writing of writing in the third person, and avoid writing in the first person. But that is not the same issue. There is much confusion around this. Authors often go to great lengths to avoid active voice and especially to avoid writing in the first person. Just to clarify: if the verb relates to the person or thing, then we are using active voice, whereas if the verb is not connected to the doer, then passive voice is used. For example, in the preceding sentence, “use” appears in both voices, first actively then passively. The differences between first and third person is, perhaps, a little more straightforward.
Active voice is good, if you want to engage the reader. Passive voice is good if you want to stand to one side and deal with the data, analysis and conclusions dispassionately. The confusion arises when authors try to make the work look objective by changing “I” to “the writer” or “the author”, which is just a clumsy way of revealing that they do not know what this active/passive thing is all about! So rather than writing “the author of the present paper considers …”, which is active voice in the third person, use “it is considered …”, which is passive. I am sure you can think of many more examples!