Coding With Doubly Linked Lists

Veritas Technologies keeps a small in-memory doubly linked list inside its backup-catalog service to track the most recently touched backup jobs, so the most recent one can be found and removed quickly without rescanning the whole job list. A teammate wrote the class below to add jobs, delete a job by id, and read job ids in from the console, but it's already causing incorrect "recently touched" lists in staging.

class Node:
    def __init__(self, job_id):
        self.job_id = job_id
        self.prev = None
        self.next = None


class JobList:
    def __init__(self):
        self.head = None
        self.tail = None

    def add_front(self, job_id):
        node = Node(job_id)
        node.next = self.head
        self.head = node
        self.tail = node

    def delete(self, job_id):
        current = self.head
        while current.job_id != job_id:
            current = current.next

        if current.prev:
            current.prev.next = current.next
        if current.next:
            current.next.prev = current.prev

    def to_list(self):
        result = []
        node = self.head
        while node != self.tail:
            result.append(node.job_id)
            node = node.next
        return result


def load_jobs():
    jobs = JobList()
    raw = input("Enter job ids separated by spaces: ")
    for job_id in raw.split():
        jobs.add_front(job_id)
    return jobs

Walk through what happens when a few job ids are added and then one is deleted, and explain in writing everywhere this implementation loses or corrupts data.