One thing that inspired me to visit Rome and go sightseeing was the immense number of movies that were filmed there. Movies such as Angels & Demons, The Talented Mr. Ripley, Eurotrip and more were filmed in Rome (Some movies only parts of it were filmed in Rome). I wanted to see all the sights I have seen in the movies and also those hidden to the typical tourist.
I visited Rome in the summer a few years back. Although friends and family suggested me to go in a different time frame, I decided to go against them and see the beautiful city in August, because I expected it to be less crowded with tourists. I must say I was not disappointed as the Rome quickly became my favourite city in Europe.
The only bad thing was the scorching hot weather in the afternoon, a problem, which I solved with waking up everyday at 5 in the morning to see the sights, and relaxing later when it was the hottest part of the day. Of course in the evenings, I went exploring again.
All in all, after my 1st visit, I decided to visit Rome every few years, and maybe move there permanently as I feel the city itself is very relaxing to the soul.
I recommend visiting Rome if you have the chance, as it is even more beautiful in person. The city, its architecture, the locals, the culture really makes an everlasting impression.