Some bizarre misunderstandings on this thread
No-one who wants to 'get sectioned' should be because if they want to be admitted and treated it should just be done voluntarily (informally). If someone is asking to 'get sectioned' then no wonder they aren't. Do people mean 'asking to be admitted'?
Being detained under MHA is and should be a rare thing. It is taking away a persons liberty and treating them against their will when they haven't done anything wrong. This is a draconian step and can only be done if the person's mental illness is severe, causing a risk AND all voluntary treatment options have been refused or exhausted. People who are mentally ill still have rights and choices and are allowed to refuse treatment and behave oddly or anti-socially just like anyone else as long as they are not a risk.
Yes more people with BPAD and schizophrenia would be detained than with depression because they often lack insight into their illness. People with depression in most cases want to be treated and therefore don't need to be detained
If you are already admitted and ask to leave you can be placed on a 72h holding order called S5,2
but in no way is this automatic. Most people who ask to leave can just leave especially if they agree to community treatment. It's only if a Dr determines they are at high risk that they would be detained.
Even if you are placed on S5,2 it does not automatically go on to S2 (28 days max) or S3 (6 months max). S5,2 and S136 (police holding power) aren't really 'being sectioned'. These are for being held for assessment for a short period and may not then be detained.
People who are detained have rights to appeal, their 'nearest relative' has a right to discharge them and they have a right to a 2nd opinion about medication if on S3. 2 Drs and an AMPH have to agree before a person can be detained so it's not really simple to even arrange an assessment. It will usually take most of a day to arrange all the right people to attend. Detention is actually more about giving the person rights and ensuring they are not locked up without recourse to appeal.
There's a million reasons why detention under MHA is not easy or frequent and nor should it be.