I read many books about how to design great software, but I kind of struggle to come up with a good design decisions when it comes to business apps, especially when the timeframe is tough.

In the company I currently work for, the following situation happen all the time: my teamlead tells me that there's a task to do, I call some guy or a girl from business who tells me exactly what is it they want, and then I start coding. The task always fits in some existing application (we do only web apps or web services), usually it's purpose is to pull data from one datasource and put into the other one, with some business logic attached in the process.

I start coding and then, after spending some time on a problem, my code didn't work as expected - either because of technical mistake or my lack of knowledge of the domain. The business is ringing me 2-3 times a day to hurry me up. I ask my team lead to help, he comes up, sees my code and goes like 'What's this?'. Then he throws away about half of my code, including all the design decisions I made, writes 2-3 methods that does the job (each of them usually 200-300 lines long or more, by the way), and task is complete, code works as it should have. The guy is smarter than me, obviously, and I'm aware of that.

My goal is to be better software developer, that means write better code, not finish the job quicker with some crappy code. And the thing is, when I have enough time to tackle a problem, I can come up with a design that is good (in my opinion, of course), but I fall short to do so when I'm on a tight deadline. What should I do?

I am fully aware that it's rather vague explanation, but please bear with me