We all know that the obligatory prayers are better said in a congregation. This multiples the reward many times over than when the prayer is said alone.

The Prophet Muhammed (SAW) said:

“Verily, the best prayer of a person is in his house, except for the obligatory prayers.” - Buhkari

“Perform some of your prayers in your homes, and do not turn them into a graveyard (place where prayer is not observed).” - Buhkari, Muslim 

“The voluntary prayer of a man in a place where no person can see him is equal to twenty five times his prayer where people can see him.” - Musnad Abu Ya’laa 

The above hadiths shows us that our sunnah prayers should be said at home and somewhere private in order to increase our rewards. This includes the sunnah prayers such as Witr and Salatul Duha. Saying these prayers at home also help:

1. Makes one humble and prevents one from showing off
2. Helps in attaining Khushoo
3. Mercy of Allah descends on the home
4. Causes Shaytan to leave the home
5. It multiplies the rewards of the voluntary prayer, similar to how the rewards of the obligatory prayers are multiplied by performing them in a congregation in a Masjid.

The Prophet Muhammed (SAW) said: “The superiority of the prayer of a man in his house over his prayers (in a place) so that the people can see him, is like the superiority of the obligatory prayer over the voluntary.” - Saheeh At-Targhib

Abdullah bin Shaqiq said: "I asked Aisha (RA) about voluntary prayers of the Prophet (SAW) and she replied: ‘Before Dhuhr, he used to pray 4 rakahs in his house, then go out to lead the people in prayer, then come in and pray two rakahs. He would lead people in Magrib, then come in and pray two rakahs. Then he would lead people in Ishai and enter my house and pray 2 rakahs. He would pray 9 rakahs during the night including witr. At night, he would pray for a long time standing and for a long time sitting; and when he recites the Quran while standing, he would bow and prostrate himself from the standing position.and when he recited while sitting, he would bow and prostrate himself form the sitting position. And when it was dawn (Fajr), he would pray 2 rakahs.” - Muslim

And Allah knows best. May Allah forgive me if I am wrong and guide us all unto the right path. Ameen.