Generally refusing to make use of talents and potentialities granted by Allah is kind of miserliness.
قال علی علیه السلام
الْبُخْلُ عَارٌ وَ الْجُبْنُ مَنْقَصَةٌ وَ الْفَقْرُ يُخْرِسُ الْفَطِنَ عَنْ حُجَّتِهِ وَ الْمُقِلُّ غَرِيبٌ فِي بَلْدَتِهِ.[1]
Amir al-mu'minin (as) said: Miserliness is shame; cowardice is a defect; poverty disables an intelligent man from arguing his case; and a destitute person is a stranger in his home town.
Miserliness is shame because it is morally reprehensible and the miserly person always gets blame for his dependence on material goods. In a noble hadith form Imam al-Sadiq (a.s) greed and miserliness are counted as two elements out of 8 pests of individuals with knowledge (ulama) Imam brings the verse of Quran which reads:
Only those of Allah's servants having knowledge fear Him[2]
After stating that "the fear (from Allah) is the Heritage of knowledge" then he counts 8 pests of people with knowledge beginning by greed and miserliness.[3]
It seems miserliness here means to avoid utilizing the knowledge by teaching others, in the sense that almsgiving of knowledge is spreading and teaching others.[4] In short, miserliness is shame according to what Imam Ali (a.s) stated and miserliness also can have different perspectives in knowledge, advising, money and etc. Generally refusing to make use of talents and potentialities granted by Allah is kind of miserliness.
Notes:
[1] Nahj al-Balaqa. Hadith No. 3
[2] إِنَّمَا يخَشىَ اللَّهَ مِنْ عِبَادِهِ الْعُلَما 35:28
[3] Misbah al-shri'a. P 21
[4] Usul al-Kafi.V 1. P 41. ٍ عَنْ جَابِرٍ عَنْ أَبِي جَعْفَرٍ ع قَالَ: زَكَاةُ الْعِلْمِ أَنْ تُعَلِّمَهُ عِبَادَ اللَّه
Al-Hayat.part Tazyeel in Chapter 41. Hadith No 9. الإمام على «ع»: زكاة العلم، نشره