My project late for 2 weeks to deliver to our client cause of my dev,

Me: When you will finish your task?
Dev: this weekend, it’s only bla bla bla

But he never finish his task on time.

I am plan to cut $100 from his bonus to buy new chair for us, what do you think? Or any idea?

PS: My dev will see this rant

I'd like you to explain "blah blah blah" before anything else.

@d02d33pak yeah need those 'blah blah blah ' words

@d02d33pak mostly documentation of his code

Cutting his bonus won't make him faster the next time.
Ask him why it didn't worked out and see if there is something to solve for the future.
When somebody says 'this weekend', your alarmclocks should go on and all red flags should be waving.
Developers need time to rest as well, and thats mostlyon the weekend.

P.S. estimation for complex stuff is not easy.

How was the time it will take your dev estimated? Was he_she asked or did you/your client set a deadline? Where there different small goals with their own estimates to see if the development is on track? If so you should see, what took longer and have a feedback round, why that was and how to prevent it in the future.

@edXius always ask nicely to your programmer.

Time estimation for projects is the most difficult thing I have yet encountered.

Often, I try to estimate project length in days, and multiply that number by 7 -- it's often more accurate. There are always unexpected complications, and some of them add days of effort and/or troubleshooting.

Instead of seeing projects as a group of straightforward tasks to accomplish, look at them as a series of complex, often interconnected logic problems. You'll begin to understand why estimating is so difficult.

Basically, projects will be done when they're done. No amount of pushing or begging or guilting will change that.

@Ashkin
Please change the background color so that we can see that post bird properly. 🙂