Of late, I have had the dismal experience of listening to and reading the disdainful opinions of many a self-proclaimed critics of religion and Islam, and most of them have very disrespectful and blasphemous things to say about the Quran.
So the question arises, that even though the Quran is undoubtedly a glorious, unparalleled book of guidance, mercy, healing, and spirituality, why do so many people, both Muslims and non-Muslims, misinterpret its verses and do not get guided towards Islam, i.e. towards submitting themselves humbly to Allah, even after reading it and perusing it deeply and analytically, numerous times?
Seeking Guidance From The Quran
The Effect of Intention
The state and purity of the heart of a person greatly determines how fast and how much they will receive guidance from the Quran once they start to read, study and ponder upon it.
It is the intention inside their hearts with which they approach the Quran, which becomes the crucial determining factor of whether this Glorious Book becomes a source of Divine Guidance for them, or embodies merely a written piece of text that they read to glean information about Islam, Prophet Muhammad (PBUH), and poignant events in Islamic history.
In the Quran itself, Allah has described how the Quran guides only those whose hearts are humble, submissive, and receptive to being guided: 
Verily, in this is a Message for anyone who has a heart, or who gives ear, and earnestly witnesses (the truth).
In essence, the light of guidance of the Quran does not enter a hard, blackened heart that does not believe in Allah or does not seek to be guided towards Him, i.e. a heart that does not harbor the burning desire to be guided towards the truth.
According to the Quran itself, it is a source of guidance, yes, but only for a person who believes in Allah and becomes conscious of obeying or disobeying Him i.e. the person possesses Taqwa: 
This is the Book; in it is guidance sure, without doubt, for those who are conscious of Allah.
Solitary Reading of The Quran
Many a people come back towards Allah after they encounter and endure extremely distressful and difficult situations. The Quran becomes a source of peace, guidance and mercy for anyone who seeks to become closer to Allah, but it is all the more so for those with a broken soul and a shattered will who want to turn back towards Allah in repentance and submission after they have endured hardship, loss, grief or calamity in life.
Nevertheless, although reading the translation of the Arabic text of the Quran, and reflecting upon its meanings alone, in privacy, is very beneficial for the believer who is new to the world of Islam and who does not yet possess greater, more in-depth knowledge of Islam, it is only the tip of the iceberg.
There comes a point in the life of every student of Islamic knowledge, young or old, when reading the translations of the Quran (and Ahadith) is just not enough for them. They start pining to understand the language of the Quran directly.
That is because they begin to realize that they are reaching out to Allah via the work of His creation, i.e. by reading the meanings of its text in another language that was a human effort to decode the Spoken Word (Kalam) of their Lord.
Staying Clear of The Devil’s Shenanigans
The last thing that I want to point out as a very important factor that one must give heed to while endeavoring to reflect upon and understand the Quran, is the absolute necessity of steering completely clear of any misinterpretations of its verses and distorted meanings derived from its text.
One must acknowledge and be wary of Satan who is working day and night to mislead humankind from the Right Path.
However, it is easy for Satan to mislead those humans who are still far away from the Quran. It is with the devout Muslims that Shaytaan employs more devious shenanigans in order to deviate them.
One of the strongest plots that the armies of Iblis use to mislead religiously inclined people, i.e. those who study and propagate the Quran, is to make them glean unauthentic and baseless interpretations of the Quran text; to keep them involved in innovations; and to involve them in useless, time-wasting arguments with each other regarding the meanings of the Quran.
The one who seeks to gain deeper understanding of the Quran must always remember that Allah has taken it upon Himself to protect the Quran from deliberate distortion, which all the previous Scriptures were subjected to by human beings, for personal gains.
Therefore, when seeking to reflect deeper into the meanings of the Quran, it is important to bear in mind that this is the only Book of Allah that has been hitherto interpreted correctly in the mainstream school of Islamic scholarly thought, and has hence remained free from deliberate errors or manipulations, Alhamdulillah!
Keeping a strict check on one’s Aqeedah (belief); joining the circles of knowledge; continuing to recite and study the Quran in solitude with deep reflections and ponder; and steering clear of wrong company, writings and propaganda such as anti-Islamic/Islamophobic atheists and apostates, are all necessary steps that someone needs to undertake as part of a holistic approach towards understanding the Quran correctly in order to become closer to Allah.
- The Quran 50:37
- The Quran 02:02