Work is more fun when the things you create mostly works. When fixing bugs, the probability of introducing new bugs is reduced. Specifications of program behavior expressed as tests are easier to maintain than tutorial code or a word document specification. In order to be able to write unit tests easier you are forced to simplify your classes.  Switching underlying technology or infrastructure. For example: If you have integration tests on your database repositories or data access layers it is e[...]

In real life you choose what parts to level, what to learn. As a developer do you choose to level up or are you stuck fighting the same kind of problems without gaining XP?  As a developer do you choose to spend your experience: Learning to talk to customers Learning to work with others Learn patterns, how to write prose Learn new technologies Learn how to write tests Learn how to automate tasks (build, installation, et.c.) This is just a short list. What I mean is that you have a possibility to choose [...]

In real life you choose what parts to level, what to learn. As a developer do you choose to level up or are you stuck fighting the same kind of problems without gaining XP?  As a developer do you choose to spend your experience: Learning to talk to customers Learning to work with others Learn patterns, how to write prose Learn new technologies Learn how to write tests Learn how to automate tasks (build, installation, et.c.) This is just a short list. What I mean is that you have a possibi[...]

There are no automated tests of enterprise library in the source code. Avoid if possible.

The number of test needed for a given functionality in a program is proportional to the probability of unique errors weighted by the business value of correctness for that given functionality.