Some of the Salaf used to say:
“Indeed Allâh, the Most High, has made the month of Ramadân as a competition for His creatures, in which they may race with one another to His pleasure, by obeying Him. Thus, one group comes first and so they prosper and another group comes last and so they fail.”
Latâ’if-ul-Ma’ârif of Ibn Rajab: page 246
Tawheed First 
Quote was originally retrieved from Saalih Al Fawzaan’s article “The Approach of Ramadan”