I agree 110%. And it is also the involvement of a caring mother or father teaching the Qur'an in short, but frequent sessions (2 to 3 x per day) with joy and fun. Alhamdulillah, I was able to teach my children to sight read from Noorani beginning 2 years 4 months, until the age of 4 years 1 month, masha'Allah; and they are able to accurately sight-read and recite with tajweed directly from the mushaaf from Surah al-Balad to Surah al-Naas, masha'Allah. We are currently learning Surah al-Fajr, at a pace of one line per day from the Madinah muhsaaf, to "pre-learn" the surah, and then repeating it a minimum of 100x (over several days @ 10x each session). And we always review all previous lessons daily.
Also, as I have been told by various Sheiyoukh of tajweed, in KSA, they memorize the last 3 ajza first (backwards), or 5 or 10 ajza; and in India-Pakistan, they memorize Juz Amma and/or Juz Tabaarak and then begin with al-Baqarah; and some have even suggested memorizing backwards to Yunus, and then al-Baqarah.