Things to Remember:

• Niyyah (intention) and Ihtesab (accountability to self/ to keep a check on yourself)

Allah does not Accept any worship (ibadah or good deeds) that is done without a constant check on yourself and your intention.

• Niyyah: To fast, but only to seek the Pleasure of Allah
• Hisbah: To worship (or to perform good deeds) only to seek the rewards (ajr) that have been promised by Allah.

Hadith:

A person called out loudly and asked:

O Prophet of Allah (SAW)!

والایمان؟ 

What is eman?

Prophet of Allah (SAW) said:

الاخلاص

Hadith:

A person asked Prophet of Allah (SAW):

What is the foundation of Islam?

The Prophet (SAW) said:

Salah and zakat

The person asked again:

O Prophet of Allah (SAW)! What is eman?

The Prophet (SAW) said:

الاخلاص

The person then asked:

What is Yaqeen?

The Prophet (SAW) said:

التصدیق

For the thing that you promise with your tongue (verbally), you accept it with your heart (whole heartedly) and you act upon it.

Hadith:

In another hadith, the Prophet (SAW) explained three points which are related to Ramadan but have been linked to the condition of Ihtesab (accountability)

1.  Whoever fasted in Ramadan with eman and ihtesab, then all of his previous sins would be forgiven (but the essential condition is eman along ihtesab)
2. Whoever stood in Qiyam (prayer) in the nights of Ramadan with eman and ihtesab, all his previous sins would be forgiven (but the essential condition is eman along ihtesab)
3. Whoever stood in Qiyam during LaylatulQadr (night of Qadr) with eman and ihtesab,all his previous sins would be forgiven (but the essential condition is eman along ihtesab)

Conclusion:

To perform any good deed, you should have the niyyah (intention) and ihtesab (self۔accountability). It means that you should long and seek for the rewards (ajr) of that particular good deed that have been promised by Allah SWT۔

If a person achieves this sense of hasbah (self accountability), then no matter how long the fast is, he is no longer afraid to face the hardships of hunger and thirst because he knows the more hardships he faces, the greater his rewards would be.

If a person inculcates the sense of hisbah in him, he would never be happy when Ramadan ends. Instead, he would regret as the month of endless blessings and bounty has ended.