Order of execution for an if with multiple conditionals

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This type of evaluation is called short-circuiting.
Once the result is 100% clear, it does not continue evaluating.

This is actually a common programming technique.
For example, in C++ you will often see something like:

if (pX!=null && pX->predicate()) { bla bla bla }

If you changed the order of the conditions, you could be invoking a method on a null pointer and crashing. A similar example in C would use the field of a struct when you have a pointer to that struct.

You could do something similar with or:

if(px==null || pX->isEmpty()} { bla bla bla }

This is also one of the reasons that it is generally a good idea to avoid side effects in an if condition.

For example suppose you have: 

if(x==4 && (++y>7) && z==9)

If x is 4, then y will be incremented regardless of the value of z or y, but if x is not 4, it will not be incremented at all.

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