On the road
I have to say that praying the Rosary didn't change my routine of stopping at that small parish to say my morning prayers. So I figured it'd be better if I prayed the Rosary on my commute back home late in the afternoon, when it's more relaxed.
My commute takes 30min, give or take. However, I found myself getting home with a few beads yet to pray. Granted, I try to mean the words I pray and to turn my mind to the mysteries, at least as much as I can while driving, but I often see people taking as little as 15min to pray the Rosary!
That's when I figured that perhaps the language in which I prayed it might have something to do with my time. My first language is Portuguese and it was just more natural for me to pray a private devotion using the words I had learned since an early age. I gave English a try at the Ave Marias and, lo and behold, I could make it home with a whole Rosary prayed!
Unlike in English, which is mostly monosyllabic, the words in Portuguese, as in other Romance languages, have a few syllables. I found out that a decade in Portuguese took about 7min each, whereas in English, about 5min each. But this is my engineer's approach...