Most people don't understand a simple thing about the way Allah does things. Or what it means to Work for Allah.
When those Working for Allah issue forth -- spread out that is -- on God's earth and leave no stone unturned to invite people to come to Allah, the response to their work is far from predictable.
And far from uniform.
Sometimes it is a trickle, sometimes it is a flood. Sometimes it is a drizzle and sometimes it is a downpour.
From massive to meager, from instant to delayed, the response to your work is all Allah's doing. It is not a direct outcome of your work.
The untiring efforts of Prophet's Muhammad, Sallallahu Alaihi wa Sallam, covering a span of two decades, were, toward the end, rewarded by the floodgates of acceptance opening and men and women -- Annaas -- rushing into Islam in waves:
Wa Ra-ayitan Naasa Yadkhuloona Fi Deenillahi Afwaaaja (110:2).
Other Prophets of God, Alaihimus Salam, such as Hazrath Lut, Alaihis Salam, were left wondering if there was not a single decent human being among those they were targeting and working for so long and so hard to win over for Allah.
So much so that they ended up saying:
A-Layisa Minkum Rajulun Rasheed (11:78).
"Is there not one decent human being among you?"
Or, as in another case -- also in relation to Hazrath Lut, Alaihis Salam -- as Allah and his angels looked, before proceeding to destroy the entire community of rebels against God, and his Messenger Lut, Alaihis Salam, they could not find more than a single household in that entire community that happened to be Muslim:
Fa-Maa Wajadnaa Fihaa Ghaira Bayitin Minal Muslimeen (51:36).
Go figure Muslims!
And those of you Working for Allah: take heart!
So long as you keep doing your work, and keep doing it right, there is no such thing as failure in your lot!
It is all success -- from beginning to end.
So, just go and do your work and do it right -- the way Allah asks you do it:
Fa-Lidhaalika Fad-'u Wastaqim Kamaa Umirta (42:15).
"So, go and invite people to Allah, as you are asked to do,
And don't falter in your mission!"