Those who pretend doing the deeds for the sake of Allah (swt) but indeed, they are not, rather, their deeds are to satisfy people.
The one who make show of his prayer has just one aim that is to be pointed as worshipper, so he cares about how people look at him, without taking into consideration that Allah (swt) is looking at him. Shad’da Ibn Aws (may Allah be pleased with him) said:
“I heard the Prophet (saws) said: “The thing that I most fear for my nation is polytheism and the hidden desire, I said: O’ Messenger of Allah, may your nation have an association with Allah (swt) after you? He (saws) said: “Yes, for they do not worship the sun or the moon neither a stone or an idol, rather, they make show of their deeds”.
 Majma’ Al-Zawaed, Hadith No. 5226.