What is inferred, and from what
Structure comes from the element tree: every child of an element becomes an entry in an xs:sequence, in the order the document has them.
Occurrence comes from counting. An element that appears more than once inside any single parent gets maxOccurs unbounded. An element that appears in some parents and not others gets minOccurs zero, which is the closest a single document can get to knowing something is optional.
Types come from the values. A value that is all digits becomes xs:integer, one with a decimal point becomes xs:decimal, true and false become xs:boolean, an ISO date becomes xs:date. A value with a leading zero stays xs:string, because it is an identifier rather than a number and typing it as an integer is how a schema starts rejecting good documents.
Where one element holds different kinds of value across the document, the type widens to whatever accepts all of them. Integers mixed with decimals become xs:decimal; anything mixed with text becomes xs:string.
A schema from one document is a guess
A schema describes every document of a kind. What you have is one example of that kind, so the schema describes your example and not necessarily the family it belongs to.
Two things are worth checking by hand every time. An optional element that happens to be present in your sample is inferred as required, because nothing in the document says otherwise. And a repeating element that appears exactly once is inferred as appearing exactly once.
Feeding a larger and more varied sample fixes both, and reading the result before you use it fixes the rest. Treat the output as a first draft with the tedious part already done.
Namespaces
Namespace prefixes are kept in element names as written, and no targetNamespace is declared. A document that uses namespaces properly needs that adding by hand, along with the matching xmlns declaration.